Safeguarded delivery of goods by unmanned aerial vehicles

ABSTRACT

A control system in a delivery system performs a method to deliver a payload by an unmanned aerial vehicle, UAV, without requiring presence of the recipient even if the payload comprises sensitive or vulnerable goods. The method comprises obtaining a designated location for delivery of the payload, obtaining at least one payload vulnerability index for the payload, and obtaining a pick-up time indicative of a time point when the payload is expected to be retrieved by the recipient. The method further comprises selecting a final delivery area at or near the designated location as a function of the at least one payload vulnerability index and the pick-up time, and operating the UAV to deliver the payload to the final delivery area.

RELATED APPLICATION

The present application claims the benefit of and priority to SwedishPatent Application No. 2050342-1, filed Mar. 27, 2020, the disclosure ofwhich is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to delivery of goods by use ofunmanned aerial vehicles and, in particular, to improved safeguarding ofgoods being delivered.

BACKGROUND ART

Advancements in autonomous aerial vehicle technology are opening up newpossibilities in the area of goods delivery systems. Unmanned AerialVehicles (UAVs), otherwise known as drones, have been configured tocarry and deliver various types of goods. Such goods may, for example,include packages that would otherwise be personally delivered fromland-based delivery vehicles, such as automobiles and trucks.

One common problem in both land-based delivery and UAV delivery is thatthe recipient may not be present when the goods arrive at the point ofdelivery. Even if the delivery has been scheduled to coincide with thearrival of the recipient at the point of delivery, unforeseen eventssuch as a traffic jams may cause the recipient to be delayed. From auser perspective, it is also generally desirable that goods can beordered without requiring the recipient to be present when the goods aredelivered.

This problem is aggravated when the goods are perishable, expensive,confidential or otherwise of sensitive or vulnerable nature. Whileland-based delivery vehicles have the option of keeping the goodsonboard and rerouting for other deliveries, such options are lessrealistic and/or attractive for UAVs given their limited energy andpayload capacity.

The prior art comprises WO2019/055690 which addresses challenges thatmay occur when delivering payloads by UAVs to uncontrolled landingsites, such as residential buildings. To this end, the UAVs areconfigured to use a delivery instruction combined with computer visiontechniques to select, based on images from an onboard camera, a deliverysurface that fits the delivery instruction and has appropriatecharacteristics in terms of, for example, surface material, surfacearea, surface slope, distance to the delivery location, and distancefrom nearby objects that may obstruct the delivery.

BRIEF SUMMARY

It is an objective to at least partly overcome one or more limitationsof the prior art.

Another objective is to enable UAV delivery without requiring therecipient to be present.

A further objective is to improve UAV delivery of sensitive orvulnerable goods.

Yet another objective is to safeguard the integrity of goods that aredelivered by UAVs.

One or more of these objectives, as well as further objectives that mayappear from the description below, are at least partly achieved by amethod of delivering a payload by an unmanned aerial vehicle, a controlsystem, and an unmanned aerial vehicle according to the independentclaims, embodiments thereof being defined by the dependent claims.

Some aspects in relation to delivery of a payload by an UAV, asdisclosed herein, involve selecting a final delivery area at or near adesignated location for the delivery of the payload based on at leastone vulnerability index of the payload and based on a pick-up timeindicative of a time point when the payload is expected to be retrievedby the recipient. Thereby, the final delivery area may be tailored toone or more properties of the payload, for example to safeguard theintegrity of the payload, which may be relevant when the payloadincludes sensitive or vulnerable goods.

Still other objectives, features, aspects and technical effects mayappear from the following detailed description, from the attached claimsas well as from the drawings.

BRIEF DESCRIPTION OF DRAWINGS

Embodiments will now be described in more detail with reference to theaccompanying schematic drawings.

FIG. 1 is a block diagram of an example UAV according to someembodiments.

FIG. 2 is a diagram of a UAV approaching a designated location fordelivery of a payload carried by the UAV.

FIG. 3A is a flow chart of an example delivery method for a UAVaccording to an embodiment, FIG. 3B is a flow chart of an exampleprocedure for selecting a final delivery area in the delivery method ofFIG. 3A, and FIG. 3C is an example procedure for predicting anenvironmental condition in the delivery method of FIG. 3A.

FIG. 4 is a block diagram of an example system configured to select afinal delivery area according to an embodiment.

FIG. 5 is a flow chart of an example procedure for generatingproof-of-delivery according to an embodiment.

FIG. 6 is an overview of an example delivery system according to anembodiment.

FIG. 7 is a schematic illustration of an example delivery systemaccording to an embodiment.

FIG. 8 is a schematic illustration of an example interactive chartgenerated according to an embodiment and enabling selection of pick-upor delivery location.

FIG. 9 is a flow chart of an example scheduling method according to anembodiment.

FIG. 10 is a schematic illustration of an example partitioning of ageographic region into sub-regions, and locations of UAVs and idlepoints in relation to a potential location for pick-up or delivery.

FIG. 11A is a flow chart of an example procedure for generating anaggregated cost matrix according to an embodiment, and FIG. 11B is aflow chart of an example procedure for computing an individual costmatrix according to an embodiment.

FIG. 12A is a step-wise illustration of an example procedure forcomputing an individual cost matrix according to an embodiment, FIG. 12Billustrates a delivery task with an intermediate destination, and FIG.12C illustrates an example of an individual cost matrix computed for thedelivery task in FIG. 12B.

FIG. 13 is a conceptual view of an alignment of sub-regions inindividual cost matrices.

FIG. 14 is a block diagram of an example scheduling module according toan embodiment.

FIGS. 15A-15B are side views of an example UAV launch system accordingto an embodiment, in a default state and a launch state, respectively.

FIG. 16 is a side view of an example UAV launch system according toanother embodiment.

FIGS. 17A-17B are side views of an example UAV launch system accordingto another embodiment before and after launch, respectively.

FIGS. 18-19 are side views of example UAV launch systems according tofurther embodiments.

FIG. 20 is a block diagram of an example launch control system accordingto an embodiment.

FIG. 21 is a flow chart of an example UAV launch method in accordancewith an embodiment.

FIGS. 22A-22B are side and top views of example UAV flight paths from alaunch system location to a destination.

FIG. 23A is a schematic view of example clusters generated for aplurality of destination locations of a delivery system, and FIGS.23B-23C are flow charts of methods for configuring a delivery system

FIG. 24 is a schematic view of an example delivery system.

FIG. 25A is a schematic illustration of UAVs included in an exampledelivery system, and FIGS. 25B-25C are top plan views of exampleformations of UAVs on mission to deliver and/or pick up goods.

FIG. 26 is a flow chart of an example method of controlling a group ofUAVs according to an embodiment.

FIGS. 27A-27B are top plan views of an example group of UAVs on missionto deliver goods, illustrating example arrangements of UAVs based on airresistance.

FIG. 28 is a flow chart of an example procedure for determining relativepositions of UAVs.

FIGS. 29A-29C are flow charts of example procedures for determining airresistance of UAVs.

FIG. 30A is side view of forces acting on a UAV in transit, and FIG. 30Bshows an example definition of an orientation parameter of the UAV.

FIGS. 31A-31B are top plan views of an example group of UAVs with amaster and illustrates example data paths within the group, and FIG. 31Cis a top plan view of an example group of UAVs without master andillustrates a data exchange and a resulting switch of position.

FIG. 32 is a schematic illustration of a group of UAVs in relation toUAVs joining and leaving the group.

FIGS. 33A-33C illustrate an example delivery system configured inaccordance with an embodiment.

FIGS. 34A-34D are flow charts of example methods of configuring adelivery system for delivery of goods by use of UAVs according toembodiments.

FIGS. 35A-35E are overviews of an example configuration method accordingto an embodiment.

FIG. 36 is a block diagram of an example control system for a deliverysystem according to an embodiment.

FIG. 37 is a block diagram of a machine that may implement methods,procedures and functions as described herein.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Embodiments will now be described more fully hereinafter with referenceto the accompanying drawings, in which some, but not all, embodimentsare shown. Indeed, the subject of the present disclosure may be embodiedin many different forms and should not be construed as limited to theembodiments set forth herein; rather, these embodiments are provided sothat this disclosure may satisfy applicable legal requirements.

Also, it will be understood that, where possible, any of the advantages,features, functions, devices, and/or operational aspects of any of theembodiments described and/or contemplated herein may be included in anyof the other embodiments described and/or contemplated herein, and/orvice versa. In addition, where possible, any terms expressed in thesingular form herein are meant to also include the plural form and/orvice versa, unless explicitly stated otherwise. As used herein, “atleast one” shall mean “one or more” and these phrases are intended to beinterchangeable. Accordingly, the terms “a” and/or “an” shall mean “atleast one” or “one or more”, even though the phrase “one or more” or “atleast one” is also used herein. As used herein, except where the contextrequires otherwise owing to express language or necessary implication,the word “comprise” or variations such as “comprises” or “comprising” isused in an inclusive sense, that is, to specify the presence of thestated features but not to preclude the presence or addition of furtherfeatures in various embodiments. The term “compute”, and derivativesthereof, is used in its conventional meaning and may be seen to involveperforming a calculation involving one or more mathematical operationsto produce a result, for example by use of a computer.

As used herein, the terms “multiple”, “plural” and “plurality” areintended to imply provision of two or more elements, whereas the term a“set” of elements is intended to imply a provision of one or moreelements. The term “and/or” includes any and all combinations of one ormore of the associated listed elements.

It will furthermore be understood that, although the terms first,second, etc. may be used herein to describe various elements, theseelements should not be limited by these terms. These terms are only usedto distinguish one element from another. For example, a first elementcould be termed a second element, and, similarly, a second element couldbe termed a first element, without departing the scope of the presentdisclosure.

Well-known functions or constructions may not be described in detail forbrevity and/or clarity. Unless otherwise defined, all terms (includingtechnical and scientific terms) used herein have the same meaning ascommonly understood by one of ordinary skill in the art to which thisdisclosure belongs.

Like numerals refer to like elements throughout.

Before describing embodiments in more detail, a few definitions will begiven.

As used herein, “unmanned aerial vehicle” (UAV) refers to an aircraftwithout an onboard human pilot. The UAV may be controlled by an onboardautomated control system, a ground-based control system or by aground-based human pilot. Such an aircraft is also known as a drone oran “uncrewed aerial vehicle”. Other synonyms or variants encompassed bythe term UAV as used herein comprise RPAS (Remotely Piloted AircraftSystem), UAS (Unmanned Aircraft System), MAV (Micro Air Vehicle), andsUAS (small Unmanned Aircraft System). Examples of UAVs includemulti-rotor drones (such as tricopters, quadcopters, hexacopters,octocopters, etc.), fixed-wing drones, single-rotor helicopter drones,and fixed wing hybrid VTOL (vertical takeoff and landing) drones. TheUAV may, but need not, comprise a propulsion system.

As used herein, “payload” refers to any load carried by a vehicleexclusive of what is necessary for its operation. The payload maycomprise any type of item to be delivered by the vehicle, for example toa final destination or an intermediate storage. For example, the payloadmay comprise goods or merchandises, optionally contained in one or moreparcels, packages, containers, bags, etc.

Embodiments relate to various aspects of systems and methods that atleast partly rely on UAVs for goods delivery. The following descriptionis separated into Chapters 1-5 dealing with inventive concepts forUAV-based delivery. The separation into chapters is made for clarity ofpresentation and does not imply that the concepts cannot be combined. Onthe contrary, the concepts and embodiments thereof may indeed becombined in various constellations to achieve corresponding synergisticeffects, as will be appreciated by the persons skilled in the art.

Generally, a UAV for use in a delivery system may be considered tocomprise a main body or structure, a control system, and a mechanism forholding a payload. The control system comprises logic which isconfigured to control the operation of the UAV. The logic may beimplemented in hardware, software or a combination of both hardware andsoftware.

A detailed example of a UAV is depicted in FIG. 1. As shown, the UAV mayinclude a propulsion system 1002, control surfaces 1003, a deliverymechanism 1004, a flight controller 1005, a peripherals interface 1006,one or more processors 1007, a memory controller 1008, a memory 1009, apower system 1010, an external port 1011, a GNSS module 1012, acommunication interface 1013, audio circuitry 1014, a proximity sensor1015, an inertial measurement unit (IMU) 1016, an imaging devicecontroller 1017 and one or more associated imaging devices 1018, and anyother input controllers 1019 and input devices 1020. One or more ofthese components may communicate over one or more communication buses orsignal lines as represented by arrows in FIG. 1.

FIG. 1 is only one example of a UAV system. A UAV may thus include moreor fewer components than those shown in FIG. 1, may combine two or morecomponents as functional units, or a may have a different configurationor arrangement of the components. Some of the various components shownin FIG. 1 may be implemented in hardware, software or a combination ofboth hardware and software, including one or more signal processingand/or application-specific integrated circuits.

In some embodiments, the propulsion system 1002 may comprise one or moreof a fixed-pitch rotor, a variable-pitch rotor, a variable-pitch jetengine, or any other mode of propulsion having the effect of providing athrust force. The propulsion system 1002 may be operable to vary theapplied thrust force, for example via an electronic speed controllervarying the speed of each rotor. Further, according to some embodiments,the propulsion system 1002 may include a propulsion sub-system dedicatedto the delivery mechanism 1104 to enable maneuvering of a payloadindependently from the main body of the UAV.

In some embodiments, the UAV may include control surfaces 1003 such asflaps, rudders, ailerons, etc. The control surfaces 1003 may comprisecomponents for adjustment such as electric motors, cable pulley systems,or hydraulic systems.

The delivery mechanism 1004 may comprise the above-mentioned payloadholder, which may comprise a coupling operable to secure and release apayload.

The flight controller 1005 (sometimes referred to as “navigation system”or “autopilot”) may include a combination of hardware and/or softwareconfigured to receive input data (for example, sensor data from imagedevice(s) 1018 and/or proximity sensor(s) 1015), interpret the inputdata and output control signals to the propulsion system 1002, controlsurfaces 1003, and/or delivery mechanism 1004. Alternatively or inaddition, the flight controller 1005 may be configured to receivecontrol commands generated by another component or device (for example,processor(s) 1007 and/or a remote computing device), interpret thosecontrol commands and output control signals for the propulsion system1002, control surfaces 1003, and/or delivery mechanism 1004.

The peripherals interface (I/F) 1006 may couple input and outputperipherals to the processor(s) 1007 and memory 1009. The one or moreprocessors 1007 may run or execute various software programs and/or setsof instructions stored in memory 1009 to perform various functions forthe UAV and to process data. In some embodiments, processor(s) 1007 mayinclude a general central processing unit (CPU), a specializedprocessing unit such as a Graphical Processing Unit (GPUs), for examplesuited to parallel processing applications, or any combination thereof.The memory 1009 may include one or more computer-readable storagemediums, such as high-speed random access memory, and/or non-volatilememory, such as one or more magnetic disk storage devices, flash memorydevices, or other non-volatile solid-state memory devices. Access tomemory 1009 by other components such as the processor(s) 1007 and theperipherals I/F 1006 may be controlled by the memory controller 1008. Insome embodiments, the peripherals I/F 1006, the processor(s) 1007, andthe memory controller 1008 may be implemented on a single integratedchip (indicated by solid rectangle). In other embodiments, one or moreof the peripherals I/F 1006, the memory controller 1008, and theprocessor(s) 1009 may be implemented on separate chips.

In some embodiments, the UAV includes a power system 1010 for poweringits various components. The power system 1310 may include a powermanagement system, one or more local power sources such as battery, fuelcell, etc., a recharging system, a power failure detection circuit, apower converter or inverter, a power status indicator and any othercomponents associated with the generation, management and distributionof power in a computerized device.

In some embodiments, a communication module (not shown) may facilitatewired communication with other devices over one or more external ports1011. The external port(s) 1011 (for example, USB, FIREWIRE, etc.) maybe adapted for coupling directly to other devices or indirectly over anetwork (for example, the Internet, wireless LAN, etc.).

In some embodiments, the UAV may include a receiver such as a GlobalNavigation Satellite System (GNSS) receiver 1012 for obtaining aposition of the UAV. The GNSS receiver 1012 may be configured forcommunication with any satellite navigation system such as GPS, GLONASS,Galileo or BeiDou. FIG. 1 shows a GNSS receiver 1012 coupled to theperipherals I/F 1006. Alternately, the GNSS receiver 1012 may be coupledto an input controller 1019. The GNSS receiver 1012 may determine acurrent global position of the UAV based on satellite signals.

The communication interface (I/F) 1013 may facilitate transmission andreception of communication signals, for example, in the form ofelectromagnetic signals. The transmission and reception of communicationsignals may be carried out wirelessly, for example via a radiofrequency(RF) transceiver. In some embodiments, the communication I/F 1013 mayinclude RF circuitry. In such embodiments, the RF circuitry may convertelectrical signals to/from electromagnetic signals and communicate withcommunication networks and other communication devices via theelectromagnetic signals. The RF circuitry may include well-knowncircuitry for transmission and reception of communication signals,including but not limited to an antenna system, an RF transceiver, oneor more amplifiers, a tuner, one or more oscillators, a digital signalprocessor, a CODEC chipset, a subscriber identity module (SIM) card,memory, and so forth. The RF circuitry may facilitate transmission andreception of data over communication networks (including public,private, local, and wide area). For example, wireless communication maybe over a wide area network (WAN), a cellular telephone network, a localarea network (LAN), or any other mode of wireless communication. Thewireless communication may use any of a plurality of communicationstandards, protocols and technologies, including but not limited to GSM,EDGE, HSDPA, W-CDMA, CDMA, TDMA, LTE, 5G, Bluetooth, VoIP, Wi-MAX, orany other suitable communication protocol(s).

The audio circuitry 1014 may include one or more of a speaker and amicrophone and may provide an audio interface between the surroundingenvironment and the UAV. The audio circuitry 1014 may receive audio datafrom the peripherals I/F 1006, convert the audio data to an electricalsignal, and transmit the electrical signal to the speaker. The speakermay convert the electrical signal to human-audible sound waves. Theaudio circuitry 1014 may also receive electrical signals converted bythe microphone from sound waves. The audio circuitry 1014 may convertthe electrical signal to audio data and transmit the audio data to theperipherals I/F 1006 for processing. Audio data may be retrieved fromand/or transmitted to memory 1009 and/or the communication I/F 1013 bythe peripherals I/F 1006.

The UAV may include one or more proximity sensors 1015. FIG. 1 shows aproximity sensor 1015 coupled to the peripherals I/F 1006. Alternately,the proximity sensor 1015 may be coupled to an input controller 1019.Proximity sensors 1015 may generally include remote sensing technologyfor proximity detection, range measurement, target identification, etc.For example, proximity sensors 1015 may include radio-based sensors (forexample radar), audio-based sensors (for example sonar), optical-basedsensors (for example LIDAR), etc.

The UAV may include one or more IMUs 1016. The IMU 1016 may measure andreport one or more of velocity, acceleration, orientation, andgravitational forces. The IMU 1016 may include one or more subcomponentssuch as gyroscopes, accelerometers, magnetometers, etc. While FIG. 1shows the IMU 1016 coupled to the peripherals I/F 1006, it mayalternatively be coupled to an input controller 1019. Further, the IMU1016 may be supplemented or replaced by individual gyroscopes,accelerometers, magnetometers, etc.

The UAV may include at least one imaging device 1018. In the example ofFIG. 1, the imaging device 1018 is coupled to an imaging devicecontroller 1017 in an I/O subsystem (indicated by solid rectangle). Therespective imaging device 1018 may comprise imaging optics and anoptical sensor responsive to electromagnetic radiation. The respectiveimaging device 1018 may be responsive to electromagnetic radiation inany wavelength range, including but not limited to ultraviolet, visibleor infrared radiation, or any part or combination thereof. The opticalsensor may comprise a digital image sensor such as a CCD or CMOS sensor.As used herein, a combination of an optical sensor and imaging opticsmay be referred to as a “camera”. In conjunction with an imaging modulelocated in memory 1009, the imaging device(s) 1018 may capture digitalimages (including still images and/or video), which may be mono- orpolychromatic. In some embodiments, the imaging device(s) 1018 maycomprise a single fixed camera. In some embodiments, the imagingdevice(s) 1018 may comprise a camera with adjustable orientation, forexample by use of a gimbal mechanism with one or more axes of motion. Insome embodiments, the imaging device(s) 1018 may comprise a camera witha wide-angle lens providing a wider field of view. In some embodiments,the imaging device(s) 1018 may comprise an array of multiple camerasproviding up to a full 360 degree view in all directions. In someembodiments, the imaging device(s) 1018 may comprise two or more camerasplaced next to each other in order to provide stereoscopic vision. Insome embodiments, the imaging device(s) 1018 may comprise multiplecameras of any combination as described above. In some embodiments, theUAV may comprise one or more cameras dedicated for image capture fornavigation, for example using visual inertial odometry (VIO).

In some embodiments, the input controller 1019 may receive/sendelectrical signals from/to one or more other input or control devices1020, such as physical buttons (e.g., push buttons, rocker buttons,etc.), dials, touch screen displays, slider switches, joysticks, clickwheels, and so forth. A touch screen display may be used to implementvirtual or soft buttons and one or more soft keyboards and may providean input interface and an output interface between the UAV and a user.In some embodiments, the other control devices 1020 comprise a codereader for detecting machine-readable codes from payload(s) carried bythe UAV. The machine-readable codes may comprise a sequence ofcharacters, a bar code, a 2D code, etc.

In some embodiments, software components stored in memory 1009 mayinclude an operating system, and a set of modules or applications, suchas a communication module, a flight control module, a navigation module,a computer vision (CV) module, or a graphics module. For clarity, suchmodules are not shown in FIG. 1. The operating system (for example,Darwin, RTXC, LINUX, UNIX, OS X, WINDOWS, or an embedded operatingsystem such as Vx Works) may comprise various software components and/ordrivers for controlling and managing general system tasks (for example,memory management, storage device control, power management, etc.) andfacilitates communication between various hardware and softwarecomponents. The graphics module may include various software componentsfor processing, rendering and displaying graphics data. As used herein,the term “graphics” may include any object that can be displayed to auser, including without limitation text, still images, videos,animations, icons, and the like. The graphics module in conjunction witha GPU may process in real time or near real time, graphics data capturedby imaging device(s) 1018 and/or proximity sensors 1015. The CV module,which may be a component of the graphics module, may provide analysisand recognition of graphics data. For example, while the UAV is inflight, the CV module along with the graphics module (if separate), theprocessor(s) 1007, and imaging device(s) 1018 and/or proximity sensors1015 may recognize and track the captured image of one or more objectsin the physical environment. The CV module may further communicate withthe navigation module and/or the flight control module to update arelative position between the UAV and a point of reference, for examplea target object such as a payload, a delivery surface, a landing site,etc. The navigation module may determine the position and/or orientationof the UAV and other objects and provide this information for use invarious modules and applications, for example the flight control modulewhich thereby generates commands for use by the flight controller 1005.Each of the above identified modules and applications may correspond toa set of instructions for performing one or more functions describedabove. Described modules need not be implemented as separate softwareprograms, procedures or modules, and thus various subsets of thedescribed modules may be combined or otherwise re-arranged in variousembodiments. In some embodiments, memory 1009 may store a subset of themodules and data structures identified above. Furthermore, memory 1009may store additional modules and data structures not described above.

1. Safeguarded Delivery of Goods by UAVs

This part of the disclosure relates to enabling delivery of items byUAVs without requiring the consignee (for example, a user making anorder of goods for delivery) to be present when the items arrive at thedesignated point of delivery. This part of the disclosure isparticularly, but not exclusively, related to delivery of items that areof sensitive nature in one or more respects. In one example, the itemsmay have a high monetary and/or sentimental value. In another example,the items may be of confidential nature. In yet another example, theitems may be perishable and, for example, require storage at certainambient temperature, at least if a time limit is exceeded. Examples ofsuch perishable items include various food items, which may be raw orprocessed, as well as medications.

While a delivery by UAV often may be pre-scheduled to ensure that theconsignee is present to receive the items, this may be perceived aslimiting to the consignee who needs to adhere to the agreed schedule.Further, unforeseen events such a traffic jams may prevent the consigneefrom showing up at the delivery point in time for the delivery. Inconventional road-based delivery, for example by van or truck, there isan option of keeping the items onboard and re-routing for otherdeliveries. This option is less realistic for UAV delivery systems,given that UAVs generally have a limited ability to carry load and arepropelled by a local power source of limited capacity.

FIG. 2 illustrates a UAV 1 in transit for delivery of a payload 4. TheUAV 1 comprises a control system 2, a delivery mechanism 3 (cf. 1004 inFIG. 1) and an imaging device 5 (cf. 1018 in FIG. 1). The deliverymechanism 3 is releasably attached to a payload 4, which is to bedelivered to the destination indicated by X in FIG. 2. In theillustrated example, the destination comprises a residential building 10with a backyard surrounded by a fence 11. A car 12 is parked on thedriveway of the building 10.

FIG. 3A illustrates an example delivery method 20 in accordance withsome embodiments. The method 20 may be performed by the control systemof an UAV and will be exemplified with reference to the UAV in FIG. 2.Step 21 obtains the designated delivery location for the payload 4. Thedesignated delivery location, DDL, may be given in any suitable format,for example as GNSS coordinates, a street address, proprietary mapcoordinates, etc. Step 22 obtains at least one payload vulnerabilityindex, VID. The VID may be predefined for the payload 4 and indicate asensitivity or vulnerability of the payload 4 to a general or specificenvironmental condition. In some embodiments, the VID may represent amonetary or sentimental value or a confidentiality of the payload 4 andthus may indicate a vulnerability to theft. In some embodiments, the VIDmay represent a temperature sensitivity, for example to indicate avulnerability of the payload 4 to temperatures that are too high or toolow in relation to a nominal temperature. In some embodiments, the VIDmay represent an acceptable range of storage temperatures. In someembodiments, the VID may represent a moisture sensitivity of a packagingaround an item to be delivered or the item itself, or both. In someembodiments, the VID may represent a wind sensitivity, for exampleindicating the risk that the payload 4 will be carried away or damagedby wind.

Step 23 obtains a recipient pick-up time, RPT, at which the payload 4 isexpected to be retrieved from the DDL by the consignee (“recipient”).The RPT may be, and generally is, different from the time point when theUAV is scheduled/estimated to deliver the payload at the DDL (“deliverytime”). The UAV 1 may perform one or more of steps 21-23 incommunication with one or more external computing resources (not shown),which may provide one or more of the DDL, VID or RPT to the UAV 1.Alternatively or additionally, the UAV 1 may obtain one or more of theDDL, VID or RPT by detecting and interpreting one or moremachine-readable codes on the payload 4. In step 24, a final deliveryarea, FDA, is selected at or near the DDL as a function of the VID andthe RPT. In step 25, the method 20 may be concluded by the UAV 1 beingoperated to deliver the payload 4 in the FDA, for example by releasingthe delivery mechanism 3.

In some embodiments, the FDA is selected to mitigate the vulnerabilityof the payload 4 while it is located at or near the DDL during the timeperiod from delivery to RPT. Step 24 generally facilitates delivery ofpayloads by UAVs and opens up the possibility of tailoring the FDA tothe respective payload to be delivered and ensuring the integrity of therespective payload until it is expected to be picked up by theconsignee. It should be understood that while the DDL may be a specificlocation, the FDA is typically spaced from the DDL. In some embodiments,the UAV may store an area definition that specifies the limits of asearch area within which the FDA may be selected. For example, thesearch area may be given as a predefined distance to the DDL, or bydefined boundaries in relation to the DDL. In the example of FIG. 2, thesearch area may be limited to the real estate that includes the DDL, forexample the building 10, the backyard and the driveway in FIG. 2. Insome embodiments, the UAV 1 autonomously determines the limits of thesearch area, for example by computer vision analysis of images capturedby the imaging device 5 around the DDL.

In some embodiments, the FDA may be selected among a set of candidateareas, which may be predefined for the DDL or dynamically identified bythe UAV when making the delivery at the DDL. The predefined candidatearea(s) may be determined by or for the above-mentioned externalcomputing resource by computer analysis of the local topography, images,etc. and transmitted to the UAV 1. The images may, for example, becaptured by satellites and/or by one or more other UAVs, which may ormay not be part of the delivery system. Examples of candidate areas areshown in FIG. 2 and designated by 13A-13H. It may be noted thatcandidate area 13G is within a dedicated safety container 14 which isarranged on the roof of the building 10 and may or may not be closed oreven locked. In some embodiments, the UAV 1 is operable to remotely openthe safety container 14, for example by transmitting a security code toa control system of the container 14. Candidate area 13H is a safe spaceassociated with the car 12 on the driveway, for example its boot or anattached safety container, which may be similarly accessible to the UAV1.

As indicated in FIG. 3A, step 24 may comprise a step 24A of predictingan environmental condition in the set of candidate delivery areas. Insome embodiments, the environmental condition is predicted for aresidence time period that extends from the delivery time to the RPT,and the FDA is selected among the set of candidate delivery areas as afunction of the predicted environmental condition and the VID. Thepredicted environmental condition may be relevant for the VID, and viceversa. For example, the VID may indicate a vulnerability of the payload4 to the environmental condition that is predicted by step 24A. In someembodiments, the environmental condition may comprise exposure tosunlight. Such an environmental condition may be relevant to a VIDindicative of temperature sensitivity. In some embodiments, theenvironmental condition may comprise exposure to precipitation, dew orother moisture. Such an environmental condition may be relevant to a VIDindicative of moisture sensitivity. In some embodiments, theenvironmental condition may comprise exposure to wind, draught or thelike. Such an environmental condition may be relevant to a VIDindicative of wind sensitivity.

Some non-limiting examples of considerations for selecting the FDA fordelivery of an item include: finding an area in shade for a certainlength of time for keeping items cool, considering the RPT; finding anarea directly exposed to the sun for a certain length of time forkeeping items warm, considering the RPT; finding a dry surface; findingan area specified by a photograph of a section of the recipient'spremises, for example part of a garden, or a text describing a locationin the recipient's premises; finding an area immediately behind a fenceor wall, between two large structures, or on an elevated structure suchas a roof or balcony, to keep the item concealed and/or less accessibleto non-recipients; or identifying an in-vehicle option, for example theboot or a special compartment of a car owned by the recipient.

FIG. 3B is a flowchart of an example procedure for selecting the FDA. Asindicated, the example procedure may be part of step 24 in FIG. 3A. Theprocedure presumes a nominal selection of candidate areas, which isdenoted CAD0 below and may include all available candidate areas. Instep 30, the VID is evaluated to determine if the payload 4 is of highvalue, for example in terms of money, affection or confidentiality. Ifso, step 31 determines a first set of candidate areas, CAD1, thatmatches the VID by reducing the risk that the payload 4 is stolen, forexample areas that are hidden from view (“non-overlooked areas”). In theexample of FIG. 2, CAD1 may include all candidate areas except 13A. Insome embodiments, the VID may indicate different categories of value,and CAD1 may differ depending on category. For example, for the mostvaluable payloads, CAD1 may consist of 13G and 13H. With respect to 13H,step 31 may include verifying that the car 12 belongs to the consignee,for example based on the number plate of the car 12. The procedureproceeds to step 32, which evaluates the VID to determine if the payload4 is sensitive to moisture. If so, step 33 predicts the risk forprecipitation at DDL during the residence time period. Step 33 may thusbe part of step 24A in FIG. 3A. Step 33 may comprise predicting the riskfor precipitation in the available candidate areas 13A-13H, or a subsetthereof. The prediction in step 33 may be based on weather data for theDDL, for example a weather forecast for the residence time period orpart thereof. Step 33 may account not only for precipitation but alsofor the local topography (cf. 3D model, below) and/or estimated winddirections at the candidate areas. For example, candidate area 13E maybe deemed to be shielded from precipitation given its location beneath atree. Based on step 33, step 34 determines a second selection ofcandidate areas, CAD2, which is deemed to mitigate the risk that thepayload 4 is exposed to moisture. In the example of FIG. 2, CAD2 mayinclude 13E, 13G, 13H and, depending on wind direction, one or more of13B-13D. The procedure proceeds to step 35, which evaluates the VID todetermine if the payload 4 is sensitive to temperature. If so, step 36predicts the exposure to sunlight in the available candidate areas13A-13H, or a subset thereof.

An example procedure that may be performed by step 36 is shown in FIG.3C. Step 40 obtains a three-dimensional (3D) representation of the DDL.The 3D representation may be a 3D model of a region that includes theDDL. The extent of the region may be defined to include any structuresthat may cast shadows on the available candidate areas at the DDL. Suchstructures may include surrounding buildings as well as naturalformations of the terrain. Step 41 obtains weather data for the DDL orthe region, for example the above-mentioned weather forecast. Step 42then predicts the exposure to sunlight in the 3D model, for example atthe available candidate areas or a subset thereof, based on the weatherdata and movement of the sun during the residence time period. Theweather data may be used to estimate the amount of clouds and thereby alikelihood of sunlight exposure.

Reverting to FIG. 3B, step 37 determines a third selection of candidateareas, CAD3, which is deemed to match the temperature requirements ofthe payload 4 as indicated by the VID. If the payload is sensitive tohigh temperatures, CAD3 may include candidate areas with little or noexposure to sunlight. If the payload is sensitive to low temperatures,CAD3 may include candidate areas with much exposure to sunlight. Theprocedure then proceeds to step 38, which selects the FDA among theselections CAD0-CAD3, to the extent that they have been determined. Forexample, step 38 may select the FDA among the intersection of thedetermined selections CAD0-CAD3, i.e. the candidate areas that areincluded in all of the determined selections.

As indicated in FIG. 3B, the FDA may be further selected based on inputdata 219, which may be provided by the consignee, for example whenplacing the delivery order. The input data 219 may be indicative of oneor more candidate areas in the nominal selection CAD0. For example, theinput data 219 may comprise one or more photographs of suggestedcandidate areas and/or a textual description thereof.

In some embodiments, step 24 may comprise obtaining sensor data from asensor device (cf. 1018, 1020 in FIGS. 1 and 5 in FIG. 2) on the UAV orone or more other UAVs, and step 24A may predict the environmentalcondition at the DDL based on the sensor data. Such sensor data maycomprise ambient humidity from a humidity sensor, wind data (speedand/or direction) from a wind sensor, images from two or more cameras ora stereoscopic camera for determination of 3D topography, images from athermographic camera for determination of temperature or sunlightexposure, images from any type of camera for identification of shadesand/or ground moisture. Such images are non-limiting examples of 2Drepresentations that may be taken in the proximity of the DDL for use inpredicting the environmental condition. In some embodiments, the sensordata may supplement or even replace the above-mentioned weather data. Insome embodiments, the sensor data may provide or supplement theabove-mentioned 3D representation. In some embodiments, the sensor datamay enable prediction of exposure to sunlight during the residence timeperiod without the need for further weather data.

FIG. 4 is a block diagram of an example system for determining the FDA.The system comprises a computation device 50, which is configured toobtain the RPT, the DDL and the VID from one or more first modules 51(one shown) and compute the FDA in accordance with any of the methodsand procedures described herein. In the illustrated example, thecomputation device 50 is further configured to obtain the 3Drepresentation of the DDL (cf. step 40) from one or more second modules52, and weather data (cf. step 41) from one or more third modules 53. Asunderstood from the foregoing, the computation device 50 may be includedin the UAV 1, and the first module(s) 51 may be included in one or moreexternal computing resources. Optionally, a first module 52 may belocated on the UAV 1 and connected to a code reader. Likewise, thesecond module(s) 52 and third module(s) 53 may be included in one ormore external computing resources and/or be included in the UAV 1 andconnected to one or more sensor devices.

It is also conceivable that the computation device 50 is included in anexternal computing resource, which is configured to communicate the FDAto the UAV 1. For example, such an external computing resource mayperform the method 20 in FIG. 3A, or at least steps 21-24.

The method 20 in FIG. 2A further includes an optional step 26 ofgenerating proof-of-delivery when the payload has been delivered in theFDA. Step 26 may comprise operating the imaging device 5 on the UAV 1 tocapture one or more images, for example in the form of still images orvideo, that visually include the payload 4 at the FDA and provide theimage(s) as proof-of-delivery. In some embodiments, theproof-of-delivery may further comprise the above-mentioned sensor dataand/or prediction data that is relevant for the payload 4. In a specificexample, the proof-of-delivery may state that “The package has beendelivered. The current temperature is 7° C. and is expected to be 9° C.at the pick-up time, with a confidence level of 88%”.

In some embodiments, the image(s) for the proof-of-delivery may be takento fulfil at least one predefined image criterion. Such an imagecriterion may specify one or more objectively identifiablecharacteristics or visual features to be included in the image(s). Thevisual features may broadly represent the DDL or the recipient. Onevisual feature may be an identifier associated with the recipientaddress, such as a nameplate, a building or apartment sign, a numbersign, etc. Another visual feature may be an identifier associated withan object owned by the recipient, such as the license plate of therecipient's car 12. Yet another visual feature may be supplied andrequested by the recipient, for example a specific window, balcony, dooror other feature of the recipient's premises. In one example, the imagecriterion comprises a photograph provided by the recipient to beapproximately matched with an image provided with the proof-of-delivery.In some embodiments, the UAV 1 may be configured to automatically detectpresence of the visual feature(s) in the image(s), for example by use ofvision-based machine learning for object detection or the like.

FIG. 5 is a flowchart of an example procedure for providingproof-of-delivery by operating the UAV 1. As indicated, the exampleprocedure may be part of step 26 in FIG. 3A. With reference to theexample in FIG. 2, step 60 may comprise operating the imaging device 5on the UAV 1 to generate image(s) of the FDA. Step 61 evaluates if theat least one image criterion is fulfilled. If not, step 62 moves the UAV1 in relation to the FDA and/or the imaging device 5 in relation to theUAV 1, whereupon step 60 is repeated. In one example, steps 60-62 maycause the UAV 1 to adjust its position by circling and/or moving in/outwith respect to the payload 4 until the at least one image criterion isfulfilled. When the criterion is fulfilled, step 63 may transmit theimage(s) from the UAV 1 for display to the recipient in real time orsubstantially in real-time. At this time, the recipient may be given theopportunity to accept or reject the proposed delivery, as detected bystep 64. If the delivery is accepted, step 64 proceeds to step 65 whichoperates the UAV 1 to continue its mission, for example to deliveranother payload. Otherwise, step 64 may proceed to step 66 which maygive the recipient, for example through a dedicated control interface,access to the imaging device 5 and/or the flight controller (cf. 1005)of the UAV 1 while the UAV 1 continually provides real-time images fordisplay to the recipient. The control interface may also enable otherinteractions with or by the recipient, as described herein. For example,the control interface may be provided on mobile device such as asmartphone. Step 66 may limit the recipient's access, for example bylimiting the movement of the UAV 1 to a predefined airspace around theDDL. Step 66 may give the recipient the option to select a new FDA, forexample among the candidate areas and/or a selection of otherpre-calculated locations, whereupon the UAV 1 places the payload 4 atthe new FDA. If the recipient then accepts the placement of the payload4 at the new FDA, as detected by step 67, the UAV may continue itsmission (step 65). Otherwise, step 68 may operate the UAV 1 to retrievethe payload 4 and move it to a storage.

It is conceivable that the example procedure in FIG. 5 is insteadperformed before step 25, to give recipient the opportunity to accept orreject the FDA before the payload 4 is placed at the FDA. This willobviate the need for the UAV 1 to retrieve the payload 4 in case ofrejection in step 64 or 67.

FIG. 6 is a schematic overview of an example delivery system inaccordance with an embodiment. The delivery system comprises a fleet ofUAVs 1 (one shown), and a server 70 which is configured to communicatewith the UAVs 1 in the fleet. It is understood that the above-mentionedexternal computing resource(s) may include the server 70. In theillustrated example, the server 70 is also be configured to communicatewith electronic user devices 71 (one shown), which may be operated bythe above-mentioned recipients to place delivery orders with thedelivery system, optionally through a merchant or any other provider ofgoods. For example, the user devices 71 may be operated to enter the DDLand the RPT for a delivery order. The user devices 71 may also beoperated to receive and display the image(s) of the FDA as provided bystep 63 from the respective UAV 1 to the server 70. The user devices 71may also be operated to control the respective UAV 1 via the server 70in accordance with step 66, for example to change the direction of thefield of view 5′ of the imaging device 5 and/or change the positionand/or orientation of the UAV 1.

In the following, clauses are recited to summarize some aspects andembodiments as disclosed in the foregoing.

Clause 1: A method of delivering a payload (4) by an unmanned aerialvehicle, UAV (1), said method comprising:

obtaining (21) a designated location for delivery of the payload (4),

obtaining (22) at least one payload vulnerability index for the payload(4),

obtaining (23) a pick-up time indicative of a time point when thepayload (4) is expected to be retrieved by a recipient,

selecting (24) a final delivery area at or near the designated locationas a function of the at least one payload vulnerability index and thepick-up time, and

operating (25) the UAV (1) to deliver the payload (4) to the finaldelivery area.

Clause 2: The method of clause 1, wherein the at least one payloadvulnerability index represents one or more of a monetary value, atemperature sensitivity, an acceptable range of storage temperatures, amoisture sensitivity, or a wind sensitivity.

Clause 3: The method of clause 1 or 2, wherein said selecting (24)comprises: predicting (24A) an environmental condition in a set ofcandidate delivery areas, which are located within proximity of thedesignated location, the environmental condition being predicted for aresidence time period that extends from an estimated delivery time tothe pick-up time, and selecting (204) the final delivery area among theset of candidate delivery areas as a function of the predictedenvironmental condition and the at least one payload vulnerabilityindex.

Clause 4: The method of clause 3, wherein the environmental conditioncomprises at least one of an exposure to sunlight, an exposure tomoisture, and an exposure to wind.

Clause 5: The method of clause 3 or 4, wherein the environmentalcondition is predicted based on a three-dimensional model of a regionsurrounding the delivery location and weather data for the region in theresidence time period.

Clause 6: The method of any one of clauses 3-5, wherein theenvironmental condition is predicted based on sensor data from a sensordevice (5; 1018; 1020) on the UAV (1), or on another UAV.

Clause 7: The method of clause 6, wherein the sensor data comprises atleast one two-dimensional representation taken in proximity of thedelivery location.

Clause 8: The method of any preceding clause, wherein the final deliveryarea is further selected based on input data (39) which is supplied bythe recipient and indicative of at least one candidate area in the setof candidate areas.

Clause 9: The method of clause 8, wherein the input data (39) comprisesone or more of a photographic reproduction and a textual description.

Clause 10: The method of any preceding clause, further comprising:operating (26; 60) an imaging device (5; 1018) on the UAV (1) to captureat least one image of the final delivery area in accordance with atleast one image criterion.

Clause 11: The method of clause 10, wherein the at least one imagecriterion is indicative of one or more objectively identifiablecharacteristics to be included in the at least one image.

Clause 12: The method of clause 10 or 11, further comprising: providing(63) the at least one image for display to the recipient in real time orsubstantially in real time.

Clause 13: The method of any one of clauses 10-12, further comprising:enabling (66) external control, for the recipient, of at least one ofthe imaging device (5; 1018) and a flight controller (1005) of the UAV(1) while providing the at least one image for display in real time.

Clause 14: The method of any one of clauses 10-13, further comprising:operating (60-63) the UAV (1) to capture images of the final deliveryarea, while moving at least one of the UAV (1) and the imaging device(5; 1018), until the at least one image is deemed to match a predefinedimage.

Clause 15: The method of any one of clauses 10-14, wherein the at leastone image is captured after delivery of the payload (4) to the finaldelivery area to include the payload (4).

Clause 16: A control system comprising logic (1101, 1102) configured toperform the method of any one of clauses 1-15.

Clause 17: An unmanned aerial vehicle comprising the control system ofclause 16.

Clause 18: A computer-readable medium comprising computer instructions(1102A) which, when executed by a processing system (1101), cause theprocessing system (1101) to perform the method of any one of clauses1-15.

Clause 19: An unmanned aerial vehicle, configured to: obtain adesignated location for delivery of a payload (4); obtain at least onepayload vulnerability index for the payload (4);

obtain a pick-up time indicative of a time point when the payload (4) isexpected to be retrieved by a recipient; select a final delivery area ator near the designated location as a function of the at least onepayload vulnerability index and the pick-up time; and deliver thepayload (4) to the final delivery area.

Clause 20: The unmanned aerial vehicle of clause 19, which is furtherconfigured to: predict an environmental condition in a set of candidatedelivery areas, which are located within proximity of the designatedlocation, the environmental condition being predicted for a residencetime period that extends from an estimated delivery time to the pick-uptime; and select the final delivery area among the set of candidatedelivery areas as a function of the predicted environmental conditionand the at least one payload vulnerability index.

Clause 21: The unmanned aerial vehicle of clause 20, which is furtherconfigured to: predict the environmental condition based on sensor datafrom a sensor device (5; 1018; 1020) on the unmanned aerial vehicle, oron another unmanned aerial vehicle.

Clause 22: The unmanned aerial vehicle of any one of clauses 19-21,which is further configured to operate an imaging device (5; 1018) onthe unmanned aerial vehicle to capture at least one image of the finaldelivery area in accordance with at least one image criterion.

Clause 23: The unmanned aerial vehicle of clause 22, which is furtherconfigured to: enable the recipient to manipulate at least one of theimaging device (5; 1018) and a flight controller (1005) of the unmannedaerial vehicle (1) while the unmanned aerial vehicle provides the atleast one image for display in real time.

Clause 24: The unmanned aerial vehicle of clause 22 or 23, which isfurther configured to: compare the at least one image to a predefinedimage and capture images of the final delivery area until the at leastone image is deemed to match the predefined image.

2. Improved Utilization of a Fleet of UAVs for Delivery of Goods

This part of the disclosure relates to improving utilization of a fleetof UAVs in a delivery system and takes a different approach thanconventional centralized planning. Such centralized planning optimizesthe delivery system for maximum utilization and requires all tasks andparameters for a specific timespan to be given, and then constructs aplan and executes it. This timespan introduces a latency of the deliverysystem. The time span needs to be substantial, since optimizationbecomes more a function of chance if the timespan is too short. Duringits execution, the plan cannot be adapted to changes, for example newdeliveries, drone failures and unexpected weather conditions, withoutsacrificing the level of optimization. For proper optimization,centralized planning relies on access to all relevant parameters andtherefore typically relies on a multitude of real-time sensors, whichmay both difficult and costly to implement.

This part of the disclosure is not directed to a specific technique forscheduling delivery missions for individual UAVs in the fleet, butrather focuses on providing enabling features for a different type oflogistics system for the fleet of UAVs, specifically a logistics systemthat applies swarm intelligence to optimize utilization. Swarmintelligence (SI) is a well-known technical field, also known ascollective intelligence or symbiotic intelligence, which deals with thebehaviour of natural and artificial systems comprising multiple agentsthat interact locally with one another and with their environment.Specifically, SI systems lack any centralized control structure.Instead, local and to a certain degree random interactions between theagents lead to the emergence of “intelligent” global behaviour, unknownto the individual agents. The individual behaviour of the agents mayoften be described in probabilistic terms, and each agent may act solelybased on its local perception of the neighbourhood. This mechanism ofindirect coordination or self-organization is also known as stigmergy inthe art. The principle of stigmergy is that the trace left in theenvironment by an individual action stimulates the performance of asucceeding action, possibly by the same agent, but in many scenarios bya different agent. Thereby, SI systems may be both inherently flexibleand robust, as well as decentralized and unsupervised.

The principle of SI may be applied to UAV delivery by providing aninteractive ordering system, which allows users to evaluate differentlocations for delivery or pick-up of goods by a UAV based onlocation-specific transportation prices that are computed based on theorders placed hitherto, and which allows the users to place an order fordelivery/pick-up at a selected location based on the evaluation. Byproviding such an interactive ordering system that is configured topresent a transportation price that reflects the impact of a decisiontaken by a user (selection of a location for delivery/pick-up), it ispossible to configure the delivery system with a dynamically adaptingsolver for the utilization of the fleet of UAVs based on swarmintelligence, with the users being agents in such an SI logisticssystem. By distributing the choice of location to each user, and makethe users base their choice to a large extent on the impact of theirchoice on UAV utilization, the logistics system effectively utilizes theneural computing power of each user, which acts as a search function, tocreate an optimum utilization at every given moment in time. Forexample, the user is able to, via the interactive ordering system, spotpatterns over time, predict changes based on a plethora of externalfactors and, for example, wait to order a delivery/pick-up until acertain point in time, or decide to select a location that is locatedfurther away but associated with a lower transportation price. Byletting each user choose location in real-time based on a live overviewof the impact on utilization, the collective of users will seamlesslyadapt the delivery system to changes with the goal of maximizingutilization. In other words, the logistics system converges by itselfwhen each user makes their individual choice in their own best interest,for example to keep cost down.

FIG. 7 illustrates an example delivery system comprising a fleet of UAVs1. The delivery system comprises a scheduling device 100 which isconfigured to communicate with the UAVs 1 over a wireless network 101.The scheduling device 100 is further configured to perform methodsdescribed herein to determine a utilization schedule for the UAVs 1 andcommunicate time points and locations for delivery/pickup of goods toindividual UAVs 1. The scheduling device 100 is also configured tocommunicate with user devices 102 (one shown) comprising a display 103which is operable to display an interactive chart 104 generated by thescheduling device 100, as well as one or more input devices (not shown)for data entry. The user devices 102 may include any type of electronicdevice, including but not limited to a personal computer, a laptop, amobile communication device, a tablet computer, etc.

FIG. 8 shows a detailed example of an interactive chart 104, whichcorresponds to a geographic region and may include a background image ofthe region, for example a satellite photo, a map, etc. The interactivechart 104 also depicts transportation price for individual locations. Inthe illustrated example, different transportation prices are representedby curves 108 drawn through points of equal transportation prices. In analternative, the chart 104 may comprise a heatmap, which representstransportation price by different colours or shades. Alternatively oradditionally, the chart 104 may display transportation price in cleartext upon selection of a location, for example by the user positioning acursor at the location. In FIG. 8, two locations are indicated by mousecursors, associated with a transportation price of 10 USD and 45 USD,respectively. The chart in FIG. 8 is also personalized to the user inthat it includes a route to be taken by the user, from a starting point105 to an end point 106 along a movement path 107. The movement path 107may be manually entered by the user or be automatically derived from anapplication associated with the user on the user device 102 or anotherdevice. Such an application may be a digital personal assistant that haslearned user behaviour, a navigation service, etc. The black dots inFIG. 8 represent proposed locations for delivery/pickup on or near themovement path 107. The proposed locations may be determined by thescheduling device 100 to be on or near the movement path. The user mayselect any location on the chart 104 for delivery/pickup by any suitableselection action. As understood from the foregoing, the schedulingdevice 100 may update the chart 104 upon receiving the user selection,both as displayed to the user and as displayed to other users, therebyaffecting future selections by all users. As an alternative to allowingthe user to freely select a location by pointing to the chart 104, theuser may be presented with a fixed set of locations, for example as alist or a geographical chart, to select from based on the associatedtransportation cost.

FIG. 9 illustrates an example method 110 for scheduling delivery and/orpick-up of goods in accordance with an embodiment. The method 110 may beperformed by the scheduling device 100 in FIG. 7. The method 110 will bedescribed with reference to FIG. 10, which shows a geographic region120, which may correspond to the region of the chart 104 in FIG. 8 andwhich is partitioned into sub-regions (“cells”) 122. FIG. 10 also showscurrent locations of UAVs 1 within the region 120, as well as current orfuture idle points (see below) for the UAVs 1.

In the method 110, step 111 computes aggregated cost data, ACM, for thefleet of UAVs based on current and/or future locations of the UAVswithin the geographic region 120, for example given by a utilizationschedule 110′ (see below). The ACM associates a “utilization cost” withthe respective cell 122, where the utilization cost of a cell 122represents an estimated cost value for directing at least one of theUAVs 1 to this cell 122. As used herein, “cost” or “cost value” need notbe a monetary value but may be given in any type of unit. In someembodiments, the utilization cost corresponds to a distance, which maybe a physical distance in two or three spatial dimensions. It is alsoconceivable that the distance comprises further non-spatial dimensions,for example to account for wind direction, wind speed, etc. In someembodiments, the utilization cost corresponds to an energy consumption.The ACM may be represented as a matrix. As used herein, a matrixgenerally refers to any form of addressable data structure, for examplean array of any dimension, comprising values in any format.

Step 112 receives a query indicative of one or more potential locationsfor delivery/pick-up of a payload. The query may be generated based on auser selection, for example by the user submitting a request for placingan order for delivery or pickup of goods. Alternatively, the query maybe system-generated, for example when the user device 102 connects tothe scheduling device 100. The query may be indicative of a discrete setof potential locations, one or more coherent areas of potentiallocations within the geographic region 120, or all locations within thegeographic region 120 at a given spatial resolution. In one example, thequery may identify the user and cause step 112 retrieve the potentiallocation(s) specifically for the user, for example based on a userprofile and/or historical data. For example, the locations indicated byblack dots in FIGS. 8 and 10 may be pre-stored as potential locationsfor the user. In another example, the query may comprise the movementpath 107 (FIGS. 8 and 10) and causes step 112 to determine the potentiallocation(s) in relation to the user movement path 107, for exampleresulting in the locations indicated by black dots in FIGS. 8 and 10. Inone example, step 112 may determine the potential location(s) to havethe lowest utilization cost along the movement path 107.

Step 113 determines, based on the ACM, a transportation price for atleast one potential location among the potential location(s), and step114 presents the transportation price for the at least one potentiallocation to the user. The transportation price may be given as amonetary value, and step 113 may thus involve searching the ACM toobtain the utilization cost for the cell 122 that includes a potentiallocation, and converting the utilization cost to a transportation price.

The delivery system may be configured to allow the respective user tochange a previously selected location and/or time point fordelivery/pick-up. It is conceivable that step 113, in the event of sucha change, determines an ambient utilization cost that represents thechange in overall delivery costs for the delivery system caused by thechange, and adds the ambient utilization cost to the utilization costgiven by the ACM when determining the transportation price. It may benoted that the ambient utilization cost may be negative.

Step 114 may present a list of transportation prices for differentpotential locations. Alternatively or additionally, step 114 may presentthe chart 104 of FIG. 8 or any other graphical representation 104 of adistribution of transportation prices within the geographic region 120,or part thereof. As shown in FIG. 9, step 113 may comprise a sub-step113A of generating the graphical representation 104. Step 114 mayfurther comprise displaying the transportation price for a location thatis given by the user pointing to the specific location in the graphicalrepresentation (cf. mouse pointers in FIG. 8).

In a further variant, the query received in step 112 may be generated inresponse to the user inputting the potential location(s), for example bythe user selecting locations/areas on a displayed map of the geographicregion 120 or part thereof, by use of a mouse, stylus, finger etc.Alternatively, the user may manually enter coordinates of the potentiallocation(s) by use of a keyboard, to thereby generate the query for step112.

It is to be understood that the combination of steps 111-114 provide aninteractive ordering system, as discussed above, that allows thedelivery system to optimize its utilization based on swarm intelligence(SI).

In the example of FIG. 9, the method 110 further comprises a step 115 ofreceiving a selection by the user of a transportation price and acorresponding potential location. This selection may be indicated by theuser in any conventional way, for example by use of a mouse, keyboard,touch screen, etc. Step 115 may also comprise receiving a selected timepoint or time window for the delivery/pick-up, entered by the user,optionally in response to a set of proposed time points/windows beingpresented to the user.

Subject to the selection(s) in step 115, step 116 updates a utilizationschedule 110′ for the delivery system. The utilization schedule 110′defines current and future locations of the UAVs 1 in the fleet withinthe geographic region 120 and is thus a record of the current plan forutilization of the UAVs in the fleet. For example, the utilizationschedule 110′ may contain a list of delivery and pick-up locationsselected by users of the delivery system and associated time points, andit may also include an assignment of specific UAVs to missions involvingthe locations/time points. Step 116 may update the utilization schedule110′ by adding the location selected by the user in step 115 to theutilization schedule, optionally together with the associated time pointentered by the user. The details of the utilization schedule 110′ andits updating are implementation-specific and will not be furtherdescribed herein.

In the illustrated example, since the ACM is computed by step 111 basedon the utilization schedule 110′, a subsequent execution of steps111-116 will account for the updated utilization schedule 110′ and thusbe automatically adapted to the selection made by the user. Thereby,over time, the transportation prices will be adapted to the selectionsmade by all users in the system, resulting in an inherent convergence ofutilization as the respective user makes its individual choice in itsown best interest, for example to keep transportation price down.

Although not shown in FIG. 9, the method 110 may further comprise, forexample after step 116 in at least some repetitions, a step ofcontrolling the fleet of UAVs by directing one or more of the UAVs 1 tothe location selected in step 115 based on the utilization schedule110′.

FIG. 11A is a flowchart of an example procedure for computing the ACM.As indicated, the example procedure may be part of step 111 in FIG. 9.In step 131, individualized cost matrices for available UAVs arecalculated. The respective individualized cost matrix, ICM, defines costvalues for directing one of the available UAVs 1 to the differentsubregions 122 in the geographic region 120 (FIG. 10). Thus, in theexample of FIG. 10, there is one ICM for each UAV 1, and each ICMcomprises a cost value for each subregion 122. Each ICM may berepresented by a matrix or a corresponding data element. Subsequent tostep 131, the procedure 111 forms the ACM as a (logic) combination ofthe ICMs, which is a processing-efficient way of computing the ACM. Inthe illustrated example, the ACM is formed by steps 132-135.

In step 132, which is optional, a cost threshold is operated on theICMs, and cost values above the cost threshold are replaced by apredefined value, for example a null value. In the absence of step 132,the ACM may be generated to exhibit an excessive utilization cost forsome cells. It may be undesirable to allow the user to select a locationin such a cell, since this may force the delivery system to perform adelivery/pick-up that is unfavourable in terms of resource efficiency.Step 132 may also enable step 134 (below).

In step 133, the utilization cost is determined for the respective cell122 as a function of cost values that are associated with the respectivecell 122 in the ICMs. FIG. 13 is a conceptual view of step 133, in whichcells 122 in different ICMs are aligned and processed for generation ofthe ACM. In FIG. 13, there are N different ICMs designated by ICMi withi=1, . . . , N. FIG. 13 also shows how the cells 122 are defined inrelation to the geographic region 120.

In some embodiments, the utilization cost for a cell 122 is determinedby finding the smallest (minimum) cost value among the cost values forthis cell 122 in all ICMs. Depending on the definition of cost, this maycorrespond to identifying the UAV that has the shortest or most energyefficient path to this cell 122, where the UAV is given by the ICMcontaining the smallest cost value for this cell 122. In someembodiments, the utilization cost for a cell 122 may set to its smallestcost value. In other embodiments, represented by steps 134-135 in FIG.11A, the utilization cost for a cell 122 may be given by its smallestcost value reduced as a function of the number of available UAVs for thecell 122. In this context, the “available UAVs” may be given by all ICMsfor which the cost value is below the above-mentioned threshold. If step132 has been performed, the number of available UAVs is the number ofICMs for which the cost value of the cell 122 is not the predefinedvalue (for example, the null value). The rationale for reducing thesmallest cost value is to promote the user to select (in step 115) alocation that has several available UAVs, rather than only one or a fewUAVs, since the latter may result in an unfavourable mission in terms ofresource efficiency. Thus, in FIG. 11A, step 134 determines a count ofthe available UAVs for each cell 122, and step 135 populates therespective cell of the ACM by the smallest cost value downscaled by thecount.

In some embodiments, step 111 may comprise an interpolation step toincrease the granularity of the ACM. Such an interpolation step mayoperate on the cost values of the cells 122 determined by step 135, forexample, to generate interpolated cost values within or between thesecells 122. This is a processing-efficient way of increasing theresolution of the ACM. Any interpolation technique may be used, such aslinear, polynomial, spline, etc.

In some embodiments, step 111 may comprise a contrast enhancing step, toincrease the precision of the ACM, for example after or during theabove-mentioned interpolation step. Such a contrast enhancement step maycomprise determining the local derivative in cost values for cells 122within the ACM, and updating the cost values in the ACM based on thelocal derivatives to enhance the contrast between adjacent cells 122.

FIG. 11B is a flow chart of an example procedure for computing an ICM.As indicated, the example procedure may be part of step 131 in FIG. 11A.As noted above, the ICM is computed for a specific UAV in the fleet.Step 136 determines a starting point for the UAV in the geographicregion 120. In some embodiments, the starting point is set to thecurrent position of the UAV. Simple calculations and sufficientlyaccurate results may be obtained by setting the starting point to aposition at which the UAV 1 is scheduled to be idle. In one example, theUAV 1 is scheduled to be idle whenever it arrives at an infrastructurecomponent of the delivery system, such as a payload storage facility(warehouse, intermediate storage, etc.) or a charging station. Thepositions of such infrastructure components (“idle points”) are known,and the time points of arrival and departure for the respective UAV maybe included in the utilization schedule (110′ in FIG. 9). Reverting toFIG. 10, idle points 123 are marked by a cross, and the scheduled pathsfor the UAVs 1 from their current positions to their next idle points123 are schematically represented by solid arrows. The dashed arrows inFIG. 10 schematically represent the paths from the idle points to one ofthe cells 122.

Step 137 determines a distance value from the starting point to a cell122 for the specific UAV, and step 138 determines a cost value for thecell based on the distance value. Steps 137-138 are performed for allcells 122 in the region 120, or a subset thereof. As noted above, thedistance value may be a physical distance, but may also includenon-spatial dimensions. Step 138 may set the cost value to the distancevalue or convert the distance value in any suitable way. For example,the cost value may be computed to represent an energy consumption of theUAV. Step 138 may also account for further UAV parameters, such as thescheduled residence time (“idle time”) of the UAV at its idle point 123.For example, to promote utilization of UAVs and reduce the scheduledresidence time, the cost value may be reduced as a function of scheduledidle time.

Step 137 may account for obstacles that prevent the UAV from taking astraight path from the starting point to the respective cell. In someembodiments, a flood-fill algorithm may be applied for calculating thedistance values. One such embodiment is exemplified in FIG. 12A, whichillustrates a stepwise calculation of an ICM for a matrix of cells 122.Some of the cells are occupied by an obstacle 124 (filled squares) thatthe UAVs are deemed unable to overcome, for example by flying above aspatial obstacle. Initially the matrix is empty, except for the cellcontaining the idle point 123 which is assigned distance value 0. Thecalculation performs a sequence of iterations to determine distancevalues for all cells. Each iteration determines distance values forcells adjacent to the cells that so far have been assigned a distancevalue (“non-empty cells”). In the illustrated example, the cell width isassumed to be 1 and the elevation difference between the cells isassumed to be 0. To determine the distance value of a specific cell inan iteration, step 137 may calculate, for each adjacent cell that isnon-empty, the sum of the centre-to-centre distance between these cellsand the distance value of the non-empty cell, and set the distance valueof the specific cell to the minimum of the resulting sums. Therepetitions are terminated when all relevant cells have been assigned adistance value, which thus estimates the minimum travel distance fromthe respective cell 122 to the idle point 123. In the illustratedexample, four repetitions are required to populate the ICM.

Step 137 may also account for the current position of the UAV inrelation to the idle point 123. An example is shown in FIG. 12B, where123′ designates the current location of the UAV and 123 designates anidle point, for example a storage facility where the UAV will pick-upthe payload to be delivered and/or stop for charging. In this example,step 137 may perform a first sequence of iterations as described forFIG. 12A, using the current position 123′ as starting point, todetermine a distance value for the cell containing the idle point 123.As seen in FIG. 12A, this distance value is 3.8. Step 137 then performsa second sequence of iterations as described for FIG. 12A, using theidle point 123 as starting point and using the distance value determinedby the first sequence of iterations. The resulting ICM is shown in FIG.12C.

Step 137 may further comprise an interpolation step and/or a contrastenhancement step that operates on the ICM, for example as describedabove for the ACM.

Any available algorithm for finding shortest paths in a data set may beimplemented to populate the ICM. Examples include a flood-fillalgorithm, a Floyd-Warshall algorithm, Johnson's algorithm or any wavepropagation algorithm, such as an adapted light propagation volumesalgorithm, etc

Reverting to the method 110 in FIG. 9, it may be noted that the usersare presented with transportation prices that are based on theutilization schedule 110′ at every single point in time. It isconceivable that step 116 further updates the utilization schedule 100′based on manual or automatic prediction, for example extrapolation basedon statistics, to introduce virtual deliveries, or based on relevantevents such as changed weather conditions.

In some embodiments, the method 110 is performed for the current timepoint, irrespective of the user-selected time point when thedelivery/pick-up is to be performed. Thus, the ACM may be calculatedbased on the current positions of the UAVs, forthcoming or current idlepoints for the UAVs, etc. In such embodiments, the user-selected timepoint for delivery/pick-up may at least be accounted for when theutilization schedule 110′ is updated. As used herein, the “user-selectedtime point” may be freely selected by the user or be a time pointsuggested by the system and accepted by the user.

In other embodiments, the method 110 is performed for at least onefuture time point, which may or may not be selected by the user. Theutilization cost is likely to depend on the time of the day, given thevarying availability of users to interface with the UAVs for the pick-upor delivery. In these embodiments, the ACM may be calculated based onpredictions of future positions of the UAVs, predictions of idle pointsfor the UAVs, etc. These predictions may be based on the utilizationschedule, as well as historical data, weather forecasts, advanceinformation from merchants and similar sources.

In some embodiments, the method 110 may be configured to, in step 114,present the transportation price at the potential location(s) for asequence of time points, for example the current time point and one ormore future time points, and allow the user to select the location andtime point for delivery/pick-up based on the presented data. The spacingbetween time points may be one or more hours or one or more days. Forexample, the interactive chart 104 in FIG. 8 may be supplemented by ascrolling function, for example a time bar, that allows the user tobrowse interactive charts 104 for different time points. In suchembodiments, step 111 may compute the ACM for a plurality of differenttime points to generate a time sequence of ACMs. Step 113A may generatean interactive chart 104 for the respective ACM in the time sequence,and step 114 may provide the interactive charts 104 for display.

FIG. 14 is a block diagram of an example scheduling module 140, whichmay be included in the scheduling device 100 in FIG. 7. The module 140comprises sub-modules 141-147. A UAV cost estimator 141 is configured tocompute the ICMs for the different UAVs, designated by [ICM_(i)], forexample according to step 131. A thresholder 142 is configured toperform a thresholding operation on the ICMs, resulting in pre-processedICMs designated by [ICM_(i)′], for example according to step 132. A UAVcounter 143 is configured to count the number of available UAVs percell, resulting in counts designated by [Cj], for example according tostep 134. An aggregator 144 is configured to generate the ACM, forexample according to steps 133 and 135. A price calculator 145 isconfigured to generate transportation prices TP, for example accordingto step 113. The transportation prices TP may be generated for a firstset of set of potential locations, which may be system-generated and isdesignated by [LOC1], and/or for a second set of potential locations,which may be user-generated and is designated by [LOC2]. In theillustrated example, [LOC2] is received from a presentation controller146. Further examples of the origins of [LOC1] and [LOC2] are givenhereinabove with reference to step 112. The presentation controller 146is configured to present the transportation prices TP to the user on adisplay (cf. 103 in FIG. 7), for example according to step 114, andreceive a user selection of location, designated SL, for exampleaccording to step 115. The user selection SL is detected and output bythe presentation controller 146, and a scheduler 147 updates theutilization schedule 110′ based on SL, for example according to step116.

In the following, clauses are recited to summarize some aspects andembodiments as disclosed in the foregoing.

Clause 1: A method of scheduling transports by a fleet of unmannedaerial vehicles, UAVs (1), said method comprising:

computing (111) aggregated cost data (ACM) for the fleet of UAVs (1)based on current and/or future locations of the UAVs (1) within ageographic region (120), the aggregated cost data (ACM) associatingutilization cost with distributed sub-regions (122) within thegeographic region (120), the utilization cost of a respective sub-region(122) representing an estimated cost for directing at least one of theUAVs (1) to the respective sub-region (122);

receiving (112) a query indicative of one or more potential locationsfor pick-up or delivery of a payload (4);

determining (113), based on the aggregated cost data (ACM), atransportation price for at least one potential location among the oneor more potential locations; and

presenting (114) the transportation price for the at least one potentiallocation.

Clause 2: The method of clause 1, wherein said computing (111) theaggregated cost data comprises: computing (131) individualized costmatrices (ICMi) for the UAVs (1), the individualized cost matrices(ICMi) defining cost values for directing a respective UAV (1) to thedistributed sub-regions (122); and forming (132-135) the aggregated costdata (ACM) as a combination of the individualized cost matrices (ICMi).

Clause 3: The method of clause 2, wherein said forming (132-135) theaggregated cost data comprises: determining (133), for the respectivesub-region (122), the utilization cost as a function of cost values thatare associated with the respective sub-region (122) in theindividualized cost matrices (ICMi).

Clause 4: The method of clause 3, wherein the utilization cost for therespective sub-region (122) is determined as a function of a smallestcost value among the cost values that are associated with the respectivesub-region (122) in the individualized cost matrices (ICMi).

Clause 5: The method of clause 4, wherein said forming (132-135) theaggregated cost data comprises: determining (132, 134) a count ofavailable UAVs (1) for the respective sub-region (122), wherein theutilization cost for the respective sub-region (122) is given by thesmallest cost value reduced as a function of the count of available UAVs(1) for the respective sub-region (122).

Clause 6: The method of clause 5, wherein said determining (132, 134)the count of available UAVs for the respective sub-region comprises:counting cost values that are smaller than a threshold cost among thecost values associated with the respective sub-region (122) in theindividualized cost matrices (ICMi).

Clause 7: The method of any one of clauses 2-6, wherein said computing(131) the individualized cost matrices for the UAVs comprises:determining (136) a starting point (123) for the respective UAV (1) inthe geographic region (120), determining (137) a distance value from thestarting point (123) to the respective sub-region (122), and determining(138) a cost value for the respective sub-region (122) as a function ofthe distance value of the respective sub-region (122).

Clause 8: The method of clause 7, wherein said determining (136) thestarting point for the respective UAV comprises: determining a positionat which the respective UAV (1) is scheduled to be idle.

Clause 9: The method of clause 7 or 8, wherein the cost value for therespective sub-region (122) is further determined as a function of aresidence time of the respective UAV (1) at the starting point (123).

Clause 10: The method of any preceding clause, wherein said computing(111) the aggregated cost data comprises: determining the utilizationcost within or between the sub-regions (122) by interpolation of theutilization cost associated with the sub-regions (122).

Clause 11: The method of any preceding clause, wherein said computing(111) the aggregated cost data comprises: determining a local derivativein utilization cost within the aggregated cost data (ACM) and updatingthe utilization cost within the aggregated cost data (ACM) based on thelocal derivative to enhance contrast in utilization cost betweenadjacent sub-regions (122).

Clause 12: The method of any preceding clause, further comprisinggenerating (113A) a graphical representation (104) of a distribution ofthe transportation price within the geographic region (120), whereinsaid presenting (114) comprises presenting the graphical representation(104).

Clause 13: The method of any preceding clause, wherein said computing(111) the aggregated cost data (ACM) comprises: generating a timesequence of aggregated cost data by computing the aggregated cost data(ACM) for a plurality of different time points, wherein said determining(113) the transportation price comprises: determining a time sequence oftransportation prices by determining the transportation price for the atleast one potential location at the plurality of different time points,wherein said presenting (114) comprises: presenting the time sequence oftransportation prices.

Clause 14: The method of any preceding clause, wherein the query isreceived in response to a user-selection of the one or more potentiallocations in the geographic region (120).

Clause 15: The method of any preceding clause, wherein the querycomprises a user movement path (107) in the geographic region (120), andwherein the method further comprises: determining the one or morepotential locations in relation to the user movement path (107).

Clause 16: The method of any preceding clause, further comprising:receiving (115), subsequent to said presenting (114), a user selectionof a transportation price and a corresponding potential location.

Clause 17: The method of clause 16, further comprising: including (116)the user selection in a utilization schedule (110′) that defines currentand future locations of the UAVs within the geographic region, whereinsaid computing (111) the aggregated cost data (ACM) is based on theutilization schedule (110′).

Clause 18: The method of clause 17, further comprising: directing saidat least one of the UAVs (1) to the corresponding potential locationbased on the utilization schedule (110′). Clause 19: The method of anypreceding clause, wherein the aggregated cost data (ACM) comprises amatrix that associates the utilization cost with the sub-regions.

Clause 20: A device for scheduling transports by a fleet of unmannedaerial vehicles (1), said device comprising logic (1101, 1102)configured to perform the method of any one of clauses 1-19.

Clause 21: A delivery system comprising a fleet of unmanned aerialvehicles (1), and the device according to clause 20, wherein the deviceis configured for communication with the unmanned aerial vehicles (1).

Clause 22: A computer-readable medium comprising computer instructions(1102A) which, when executed by a processing system (1101), cause theprocessing system (1101) to perform the method according to any one ofclauses 1-19.

3. Improvements in Launching UAVs

This part of the disclosure relates to launching of UAVs and is based onthe insight that the performance of UAVs may be significantly improvedby elevating the UAVs before they are launched, by use of a power sourcethat is external to the UAVs. By elevating the UAVs, energy from thepower source is converted into increased potential energy of the UAVs.The increased potential energy may be utilized to improve theperformance of the UAVs, for example in terms of range, powerconsumption, ability to carry payload, transit time to destination,etc., and may also enable use of UAVs of simpler construction, forexample UAVs without local power source. Further, the UAVs may beelevated to avoid obstacles in the flight route. Still further, the UAVmay be elevated to enable the UAV to harvest energy by use of gravity,for example to charge a battery.

Some embodiments involve a system for launching UAVs. The launch systemcomprises a lifting arrangement which is physically separate from theUAVs and powered by a power source. The lifting arrangement is operable,before launch of an UAV, to vertically elevate the UAV. The launchsystem is useful for all UAV missions but provides distinct advantagesfor UAVs that carry a payload. The power consumption for vertical motionof the UAV depends on the total weight of the UAV, and if the payload isheavy, the power consumption may be considerable. The launch system maytherefore enable significant savings in the power consumption of theUAV. The launch system may also allow the UAV to carry more weight thanit can lift, since the UAV may be launched at an altitude above thedestination.

In the following examples, the launch system is arranged in a mobilestation, for example a vehicle, a ship, or a trailer connected to atruck. The launch system may thereby be moved into a desired geographicposition from which one or more UAVs are launched on a respectivemission. However, it is also conceivable that the station is stationary.

FIGS. 15A-15B illustrate an example launch system 200 in accordance withan embodiment. The launch system comprises a control system 203, whichis located in the station 200′ and configured to operate the liftingarrangement to vertically elevate the UAVs 1 to one or more selectedheights. The control system 203 may comprise control electronics forgenerating control signals to one or more actuators (not shown) of thelifting arrangement. Such actuator(s) may be electrically, hydraulicallyor pneumatically operated. The system also comprises a system powersource 204 which is ground-based and supplies power for operating thecontrol system 203 and thereby the lifting arrangement. The system powersource may comprise a battery, a fuel cell, a combustion engine, a solarpanel, a wind turbine, etc., and/or be connected to a power distributiongrid. In the illustrated example, the lifting arrangement comprises anextendable mechanical structure 202A, for example a telescopic device ormast, a pivotable device, a bay lift, a 4-bar linkage, etc. Theextendable structure 202A is mechanically connected to a platform 201for carrying one or more UAVs 1 to be launched. FIG. 15A shows thesystem 200 in a default state, in which the extendable structure 202A isretracted with the platform 201 and the UAVs 1 being at a default orreference level (H0 in FIG. 15B), in this example substantially flushwith the top of the station 200′. FIG. 15B shows the system 200 in alaunch state, in which the extendable structure 202A has been operatedby the control system 203 to vertically elevate the platform 201 and theUAVs 1 to a selected height (“altitude”). In the illustrated example,the platform 201 has been sequentially operated to attain heights H1, H2and H3 for launch of a respective UAV 1. As will be described in detailfurther below, the heights H1-H3 may be selectively determined for therespective UAV 1.

When one or more UAVs 1 have been launched, the platform 201 may beoperated into a predefined height, for example the reference level H0below heights H1-H3. This may reduce the power consumption of any UAVthat may need to land on the platform 201, for example a UAV 1 thatreturns after completing its mission.

FIG. 16 illustrates an example launch system 200 according to anotherembodiment. The lifting arrangement comprises an aircraft 202B, forexample a dedicated lifting UAV, which may be configured to carrysubstantial load. In one example, the aircraft 202B is a so-called“cargo drone”. Other examples of aircrafts include aerostats, airshipsand hot air balloons. The platform 201 for the UAVs 1 is arranged on theaircraft 202B and is thus vertically elevated together with the aircraft202B. If the aircraft 202B has a propulsion system, the platform 201 ispreferably arranged to be shielded from air movement caused by thepropulsion system, for example to avoid downward forces onto the UAVs 1from the air movement.

In the illustrated example, the control system 203 is located on theaircraft 202B. The aircraft 202B may comprise a local power source (notshown) which is charged by the system power source 204, for example whenthe aircraft 202B has landed on a docking station 205 on the station200′. Alternatively or additionally, the aircraft 202B may be connectedby a power cable to the system power source 204.

FIGS. 17A-17B illustrate an example launch system 200 according toanother embodiment. The lifting arrangement comprises a power cable202C, which is releasably connected to the UAV 1 for supplying energyfrom the system power source 204 to the UAV 1 while it elevates to theselected height. In this embodiment, the control system 203 is arrangedon the UAV 1 and operates the propulsion system of the UAV 1 (cf. 1002in FIG. 1) to vertically elevate the UAV. The platform 201, if provided,is fixed in the system, for example on the top of the station 200′ asshown. FIG. 17A illustrates the system 200 before launch, when the UAVsis in transit to the selected height, and FIG. 17B illustrates thesystem 200 after launch, when the control system 203 has operated aholding mechanism (not shown) on the UAV 1 to detach the power cable202C. In the illustrated example, the power cable comprises a parachute206 that may be automatically released when the power cable 202C isdetached to facilitate a controlled return path for the power cable202C. The system 200 may further comprise a hauling mechanism forpulling back the power cable 202B, for example a reeling device, as wellas an attachment mechanism for re-attaching the power cable 202B toanother UAV 1.

FIG. 18 illustrates an example launch system 200 according to anotherembodiment. The lifting arrangement comprises a flow generator 202Dwhich is operable to generate a vertical air flow towards an UAV 1. Theflow generator 202D is powered by the system power source 204. In someembodiments, the flow generator 202D is operable to lift the UAV 1 tothe selected height, subject to control by the control system 203 in thestation 200′. In other embodiments, the flow generator 202D is operatedto sustain or facilitate the vertical elevation of the UAV 1, while thecontrol system 203 is located in the UAV 1 to operate the propulsionsystem (1002 in FIG. 1) to attain the selected height. As shown, thelaunch system 200 may include a platform 201 for carrying UAVs, theplatform 201 being fixed to the station 200′ and configured to letthrough the air flow.

FIG. 19 illustrates an example launch system 200 according to anotherembodiment. The lifting arrangement comprises a conveyor device 207which is configured to lift one or more UAVs 1 onto a platform 201. Theplatform 201 is attached to an extendable mechanical structure 202A.Like in FIG. 15, the control system 203 in the station 200′ may operatethe extendable structure 202A to vertically elevate the platform 201 toa selected height and operate the conveyor device 207 to elevate theUAV(s) 1 to the level of the platform 201, for example shown in FIG. 19.

It should be noted that any combination of the examples in FIGS. 15-19is conceivable. For example, the flow generator 202D in FIG. 18 may becombined with the embodiments in FIGS. 16-17. Further, FIGS. 15-19depict non-limiting examples of launch systems and the skilled personshould be able to conceive variants and alternatives based on theforegoing disclosure.

FIG. 20 is a schematic block diagram of an example control system 203for controlling the lifting arrangement in a launch system 200. Thecontrol system 203 comprises a calculation module 210 which isconfigured to calculate the selected height for launching one or moreUAVs. In FIG. 20, the selected height is designated by HL. The controlsystem 203 further comprises a controller 211 for generating a controlsignal CS in correspondence with HL and provide CS to an actuatormechanism 212 of the lifting arrangement. The controller 211 may be ofany suitable configuration, such as a feedback and/or feed-forwardcontroller. The controller 211 may thus operate in response a signalfrom one or more sensors that measure the current height of the liftingarrangement, such as a barometer or a distance meter (radar, lidar,time-of-flight, etc). The actuator mechanism 212 will depend on the typeof lifting arrangement and will not be described further.

FIG. 21 is a flow chart of an example method 220 for launching an UAV inaccordance with an embodiment. The method 220 may be performed by thecontrol system 203. Step 221 calculates the selected height (altitude)HL for launching the UAV. The selected height HL is calculated inrelation to a reference height or reference datum, for example the meansea level (MSL) or a position on the station 200′, such as the referencelevel H0 in FIG. 15B. In step 222, the lifting arrangement is operatedto vertically elevate the UAV to the selected height. In step 223, theUAV launches from the selected height, and thereby begins its mission.In the example of FIG. 20, step 221 may be performed by the calculationmodule 210, and step 222 may be performed by the controller 211. Step223 may comprise providing a launch signal to the UAV when the liftingarrangement has elevated the UAV to the selected altitude, therebycausing the UAV to launch. The launch signal may be generated by thecontrol system 203 and transmitted to the local controller of the UAV.If the control system 203 is located in the station 200′ (FIGS. 15, 18,19), the launch signal may be transmitted by wireless communication orover wire integrated in the lifting mechanism (FIGS. 15, 19). If thecontrol system 203 is located in the UAV (FIGS. 16, 17), the launchsignal may be conveyed by wire or wirelessly to the local controller ofthe UAV. It is also conceivable that the control system 203 isintegrated in the local controller.

Step 221 may calculate the selected height HL based on parameter datathat represents the UAV to be launched, the lifting arrangement, or thesurrounding conditions between the lifting arrangement and thedestination of the UAV. Examples of such parameter data is indicated inFIG. 20. In one example, the parameter data comprises the location ofthe lifting arrangement (SP, “starting point”) and the destination forthe UAV to be launched (DP, “destination point”). The starting anddestination points SP, DP may be given as two-dimensional (2D) orthree-dimensional (3D) coordinates in any global coordinate system, forexample a geographic coordinate system. In one example, the parameterdata for the UAV may indicate the type of UAV and/or a current state ofthe UAV. The current state may comprise one or more of current weightdata (WD) for the UAV, current size data (SD) for the UAV, or currentenergy content (ED) of the local power source in the UAV (cf. 1010 inFIG. 1). If the UAV carries a payload to be delivered at a destination,WD may represent either the weight of the payloads or the total weightof UAV and payload. Similarly, SD may represent either the size of thepayload or the total size of UAV and payload. Here, size may berepresented as an area, shape, one or more dimensions, or any equivalentmeasure. In one example, the parameter data for the surroundingconditions may comprise one or more of topography data (TD) for a regioncomprising SP and DP, or current ambient data (AD) of the region. Here,TD may indicate the 3D profile of the region and include the location,extent and height of obstacles between SP and DP, and AD may indicatecurrent weather conditions, air pressure, humidity, etc. The obstaclesmay include buildings, trees, power lines, etc. In one example, theparameter data for the lifting arrangement may comprise one or more ofenergy content data (ES) of the system power source 204, and elevationspeed data (LS) for the lifting arrangement. Here, LS may indicate anominal or estimated speed for the elevation by the lifting arrangement.

Step 221 may calculate the selected height HL by evaluating theparameter data in relation to at least one predefined consumptionparameter. In one example, step 221 evaluates the parameter data byoptimizing a cost function that represents the predefined consumptionparameter(s). Such a cost function may take the parameter data as knownvariable(s) and the height parameter as unknown variable. The costfunction may be optimized by finding the value of the height parameterthat produces a maximum or minimum of the cost function, this valuerepresenting the selected height. Any suitable optimization algorithmmay be applied to optimize the cost function, including but not limitedto a gradient method such as gradient descent, coordinate descent,conjugate descent, etc., or an evolutionary algorithm such as geneticalgorithm, genetic programming, etc.

In some embodiments, the at least one predefined consumption parameterrepresents a consumption cost for performing a delivery at thedestination. In one example, the selected height HL is calculated tominimize the UAV energy consumption, and the consumption cost mayrepresent the required energy consumption of the UAV to deliver thepayload at the destination. In one example, the selected height HL iscalculated to minimize the total energy consumption to deliver thepayload at the destination, and the consumption cost may represent boththe required energy consumption of the UAV and the required energyconsumption of the lifting arrangement to vertically elevate the UAV tothe selected altitude. In one example, the selected height HL iscalculated to minimize the delivery time, and the consumption cost mayrepresent the required time for the UAV to reach the destination, fromlaunch or from when the lifting arrangement is activated to elevate theUAV. In one example, the selected height HL is calculated to minimizethe monetary cost to deliver the payload at the destination.

It may be noted that step 221 may simultaneously calculate selectedheights for a plurality of UAVs 1, for example by jointly optimizingcost functions for the different UAVs.

The underlying principles will be further described for a specificexample, in which the consumption parameter is the total energyconsumption, and the cost function comprises the following parameters:type of UAV (TYPE), weight of the payload (WD), obstacle height (OH),and the height parameter (HP) to be optimized. In this example, the costfunction C may be defined as:

C=C1(TYPE,WD)·(OH−HP)+C2(TYPE,WD)·HP

where a first function C1 provide the unit energy consumption in the UAVwhen moving upwards with the payload, and a second function C2 providesthe unit energy consumption for driving the lifting arrangement upwardswhile carrying the UAV and its payload. It is realized that the selectedheight may be determined by minimizing the cost function C.

A further simplified example is shown in FIGS. 22A-22B. A launch system200 of the type shown in FIG. 15 is arranged to launch an UAV 1 fortransit to a destination 231 (given by DP in FIG. 20). The launch system200 is located at a launch location 232 (given by SP in FIG. 20), and anobstacle 233 is located between the launch location 232 and thedestination 231. Properties of the obstacle 233 may be given by theabove-mentioned topography data TD. As indicated by arrows 236, 246 inthe top plan view of FIG. 22B, the wind pattern (for example, directionand speed) between the launch location 232 and the destination 231 isknown, for example given by the above-mentioned weather data WD. Basedon this input data, step 221 may calculate the selected height tooptimize, for example, the total energy consumption, the UAV energyconsumption or the transit time. In this calculation, step 221 mayevaluate the options of elevating the UAV 1 to a level above theobstacle 233 to provide a straight route 234 for the UAV 1 to thedestination location 231, or to elevate the UAV 1 to a lower level andhave the UAV 1 take a route 235 around the obstacle 233.

As noted above, the launch system 200 may be mobile. Consider a deliverysystem that comprises a fleet of UAVs 1 and a plurality of launchsystems 200, for example as exemplified in FIG. 24. The delivery systemcomprises a scheduling apparatus 270. The launch systems 200 arearranged on mobile stations 200′ which hold a respective set of UAVs 1.In some embodiments, the delivery system is optimized for delivery ofpayloads to a plurality of destinations by actively selecting launchpositions of one or more of the launch systems 200 in relation to theplurality of destinations.

FIG. 23B is a flowchart of an example method 250 for configuring such adelivery system. The method 250 may be performed by the schedulingapparatus 270. Step 251 obtains the plurality of destinations(“destination points”, [DP]) for delivery of payloads by the deliverysystem. Step 252 obtains the number of launch locations to be determinedby the method 250. Step 253 determines this number of locations as afunction of the plurality of destinations. Step 254 directs a set oflaunch systems 200 to the launch locations, represented by [SP] in FIG.24. Step 254 may be performed by electronic communication from thescheduling apparatus 270 to the stations 200′ and/or to drivers of thestations. Alternatively, the launch location(s) may be manuallytransferred to the drivers/stations. It should be understood that step253 may assign a subset of the destinations to the respective launchlocation, and that step 254 may transfer the subset of destinations tothe UAV(s) 1 to be launched from the respective launch location.Further, step 254 may cause the goods to be delivered to be loaded onthe respective station 200′.

The delivery system may cover a geographic region that is divided intoareas that have a respective distribution center with stations 200′. Thescheduling apparatus 270 may assign goods to different distributioncenters based on the destination of the respective goods, sort thedestinations into groups by the expected time of delivery, and thenoperate the method 250 on each group separately to determine the launchlocations 232.

FIG. 23A illustrates a plurality of destinations (filled dots) 231 forgoods to be delivered by a delivery system, and launch locations (opendots) 232 determined by the method 250 for the destinations 231. Themethod 250 may also assign a respective subset of the destinations 231to the launch locations 232. In FIG. 23A, the respective subset isindicated as a cluster 240. In some embodiments, step 253 of method 250comprises operating a clustering algorithm on the destinations 231 todetermine a number of clusters 240 that is equal to the number given bystep 252, calculating geometric centers for the clusters 240, anddetermining the launch locations 232 in relation to the geometriccenters. The launch locations 232 may be set in or near the geometriccenters taking, for example, into account the physical environment suchas availability of roads, parking, etc. The launch locations 232 may beassigned to different stations 200′, but it also conceivable one station200′ is assigned to stop at two or more of the launch locations 232.

The clustering algorithm may be configured to identify a selected numberof groups among the destinations. For example, any partitionalclustering algorithm may be used, such as k-means, minimum spanning tree(MST), squared error, nearest neighbor, k-medoids, or expectationmaximization (EM), or variants, alternatives or derivatives thereof.

In some embodiments, step 252 may obtain the number of launch locationsas a predefined value, for example from a memory. In some embodiments,the number of launch locations may be provided to step 252 by anoperator, for example as input to the scheduling apparatus 270. In FIG.24, the selected number of clusters is designated by #S. By increasingthe number of clusters, the total travel distance of the station(s) 200′increases while the total flight path of the UAVs decreases. Thus, thenumber of clusters may be adjusted by the operator to achieve a desiredbalance between the distance traveled by stations 200′ versus UAVs 1.

In some embodiments, step 252 operates the cluster algorithm on thedestination points 231 for different numbers of clusters, determines oneor more evaluation parameters for the respective clustering result, andselects the number of launch locations based on one or more evaluationparameters. Step 253 may then determine the launch locations 232 for theset of clusters that was produced in step 252 for the selected number.The evaluation parameter(s) may be a default parameter for thescheduling apparatus 270 or selected by an operator. In someembodiments, the evaluation parameter(s) may comprise a first parameter,which is related to the UAVs. For example, the first parameter mayidentify the maximum flight distance, the maximum flight time or themaximum energy consumption among the UAVs when assumed to travel fromthe geometric centers of the clusters 240 to the destinations 231 withinthe clusters. Such an UAV evaluation parameter may be used to ensurethat the clusters 240 are commensurate with the operating capabilitiesof the UAVs. If the maximum flight distance/flight time/energyconsumption is too high for a set of clusters, even when using otherclusters' stations as trampolines, it may be inappropriate or evenimpossible to assign UAVs to perform deliveries in accordance with theset of clusters. In some embodiments, the evaluation parameter(s) maycomprise a second parameter, which is related to the stations 200′. Forexample, the second parameter may identify the total energy consumptionof the stations 200′ during their mission, the total distance travelledby the stations 200′ during their mission, or the time required for thestations 200′ to complete their mission. The mission may be started whenthe stations 200′ leave a distribution center and be completed when theyreturn or when all UAVs have been launched. During the mission, one orone of the stations 200′ may visit two or more launch locations.

FIG. 23C is a flow chart of an example procedure for determining thenumber of launch locations. As indicated, the example procedure may bepart of step 252 in FIG. 23B. In step 261, the current number ofclusters (#C) is set to a start value, for example a value #S entered bythe operator or a default value. In one example, the start value isequal to the maximum number of currently available stations 200′. Step262 operates the clustering algorithm on the destinations 231 to define#C different clusters. Step 263 computes the geometric centers of theclusters, and step 264 computes at least one UAV evaluation parameter asa function of the geometric centers. If the at least one UAV evaluationparameter is deemed unacceptable, step 265 proceeds to step 266 whichincreases the number of clusters (#C). When the at least one UAVevaluation parameter is deemed acceptable, step 265 proceeds to 267which computes at least one station evaluation parameter. If the atleast one station evaluation parameter is deemed unacceptable, step 268proceeds to step 266 which increases the number of clusters. When the atleast one station evaluation parameter is deemed acceptable, step 268proceeds to step 253 which may determine the launch locations for theset of clusters that was generated by the latest execution of step 262.It is realized that the procedure in FIG. 23C enables a balance to bestricken between travel parameters of UAVs and stations, by settingproper evaluation criteria, such as thresholds, for the evaluation steps265 and 268.

In the following, clauses are recited to summarize some aspects andembodiments as disclosed in the foregoing.

Clause 1: A system for launching an unmanned aerial vehicle (1), UAV, todeliver goods to a destination, said system comprising:

a lifting arrangement (202A-202D, 205, 207) which is physically separatefrom the UAV (1) and powered by a power source (204), the liftingarrangement (202A-202D, 205, 207) being operable, before launch of theUAV (1), to vertically elevate the UAV (1) to a selected altitude (HL)relative to a reference level, and a control system (203) configured tocalculate the selected altitude (HL) and provide a corresponding controlsignal (CS) for the lifting arrangement (202A-202D, 205, 207).

Clause 2: The system of clause 1, wherein the control system (203) isconfigured to calculate the selected altitude (HL) as a function ofparameter data representing at least one of the UAV (1), the liftingarrangement (202A-202D, 205, 207), or surrounding conditions between thelifting arrangement (202A-202D, 205, 207) and the destination.

Clause 3: The system of clause 1 or 2, wherein the parameter datacomprises a location of the lifting arrangement (202A-202D, 205, 207)and the destination for the UAV (1).

Clause 4: The system of any preceding clause, wherein the parameter datacomprises one or more of: topography data (TD) for a region comprisingthe lifting arrangement (202A-202D, 205, 207) and the destination,current ambient data (AD) of the region, current weight data (WD) forthe UAV (1), current size data (SD) for the UAV (1), current energycontent data (ED) of a local power source (1010) in the UAV (1), currentenergy content data (ES) of the power source (204), and elevation speeddata (LS) of the lifting arrangement (202A-202D, 205, 207).

Clause 5: The system of any preceding clause, wherein the control system(203) is configured to calculate the selected altitude (HL) byevaluating the parameter data in relation to at least one predefinedconsumption parameter.

Clause 6: The system of clause 5, wherein the at least one predefinedconsumption parameter represents a consumption cost for performing thedelivery at the destination.

Clause 7: The system of clause 5 or 6, wherein the at least onepredefined consumption parameter comprises one or more of: an energyconsumption in the UAV (1) to deliver the goods at the destination, atotal energy consumption comprising the energy consumption in the UAV(1) and an elevation energy consumption to vertically elevate the UAV(1) to the selected altitude (HL), a time period from a reference timepoint to arrival of the UAV (1) at the destination, or a monetary costto deliver the goods at the destination.

Clause 8: The system of any preceding clause, wherein the liftingarrangement (202A-202D, 205, 207) is arranged on a mobile station(200′).

Clause 9: The system of any preceding clause, wherein the liftingarrangement (202A, 202B, 207) is operable to vertically elevate aplatform (201) for carrying the UAV (1).

Clause 10: The system of clause 9, wherein the lifting arrangement(202A, 202B, 207) is configured to vertically elevate the platform (201)while the UAV (1) is carried by the platform (201).

Clause 11: The system of clause 9 or 10, wherein the control system(203) is further configured to, after the launch of the UAV (1), operatethe lifting arrangement (202A, 202B, 207) to lower the platform (201)from the selected altitude (HL) to a predefined altitude (H0).

Clause 12: The system of any one of clauses 9-11, wherein the liftingarrangement comprises a conveyor device (207) which is configured tolift the UAV (1) onto the platform (201) at least when the platform(201) is vertically elevated.

Clause 13: The system of any preceding clause, wherein the liftingarrangement comprises an extendable mechanical connection device (202A).

Clause 14: The system of any one of clauses 1-11, wherein the liftingarrangement comprises an aircraft (202B).

Clause 15: The system of any preceding clause, wherein the liftingarrangement comprises a flow generator (202D) which is arranged togenerate a vertical air flow towards the UAV (1).

Clause 16: The system of any one of clauses 1-8, wherein the liftingarrangement comprises a power cable (202C), which is releasablyconnected to the UAV (1) for supplying energy from the power source(204) to the UAV (1) while the control system (203) operates apropulsion system (1002) of the UAV (1) to vertically elevate the UAV(1).

Clause 17: The system of any preceding clause, which is furtherconfigured to provide a launch signal to the UAV (1) when the liftingarrangement (202A-202D, 205, 207) has elevated the UAV (1) to theselected altitude (HL), the launch signal causing the UAV (1) to launchfor the destination.

Clause 18: An apparatus for configuring a delivery system comprising aplurality of systems in accordance with any one of clauses 1-17, theplurality of systems being mobile and the apparatus being configured toperform a method comprising:

obtaining (251) a plurality of destinations (231) for delivery of goodsby the delivery system;

obtaining (252) a number of launch locations (232) to be determined;

determining (253) said number of launch locations (232) as a function ofthe plurality of destinations (231); and

directing (254) one or more systems among the plurality of systems tothe launch locations (232).

Clause 19: The apparatus of clause 18, wherein said determining (253)comprises: operating a clustering algorithm on the plurality ofdestinations (231) to determine a number of clusters (240) equal to saidnumber of launch locations (232), calculating geometric centers for thenumber of clusters (240), and determining the launch locations (232) inrelation to the geometric centers.

Clause 20: The apparatus of clause 18, wherein said obtaining (252) thenumber of launch locations comprises: operating a clustering algorithmon the plurality of destinations (231) in a plurality of repetitions,each repetition being configured to result in a different number ofclusters (240); evaluating (264-268) the clusters (240) resulting fromthe plurality of repetitions in relation to at least one evaluationparameter to be optimized; and setting the number of launch locations(232) based on said evaluating (264-268).

Clause 21: The apparatus of clause 20, wherein the at least oneevaluation parameter comprises a first parameter representing operationof one or more UAVs from the launch locations (232) to the plurality ofdestinations (231) and/or a second parameter representing operation ofone or more systems to launch the one or more UAVs.

Clause 22: The apparatus of clause 21, wherein the first parameterrepresents a maximum flight distance, a maximum flight time or a maximumenergy consumption among the one or more UAVs when travelling from thelaunch locations (232) to the plurality of destinations (231).

Clause 23: The apparatus of clause 21 or 22, wherein the secondparameter represents a total energy consumption for the one or moresystems, a total distance travelled by the one or more systems, or atime required for the one or more systems to launch the one or moreUAVs.

Clause 24: A method of launching an unmanned aerial vehicle, UAV, todeliver goods at a destination, said method comprising:

calculating (221) a selected altitude, relative to a reference level,for launching the UAV;

operating (222) a lifting arrangement to vertically elevate the UAV tothe selected altitude; and

causing (223) the UAV to be launched from the selected altitude.

Clause 25: The method of clause 24, wherein the selected altitude iscalculated as a function of parameter data representing at least one ofthe UAV, the lifting arrangement, or surrounding conditions between thelifting arrangement and the destination.

Clause 26: The method of clause 24 or 25, wherein the parameter datacomprises a location of the lifting arrangement and the destination forthe UAV.

Clause 27: The method of any one of clauses 24-26, wherein the parameterdata comprises one or more of: topography data (TD) for a regioncomprising the lifting arrangement and the destination, current ambientdata (AD) of the region, current weight data (WD) for the UAV, currentsize data (SD) for the UAV, current energy content data (ED) of a localpower source in the UAV, current energy content data of a power sourceproviding power to the lifting arrangement, and elevation speed data(LS) of the lifting arrangement.

Clause 28: The method of any one of clauses 24-27, wherein the selectedaltitude is calculated by evaluating the parameter data in relation toat least one predefined consumption parameter.

Clause 29: The method of clause 28, wherein the at least one predefinedconsumption parameter represents a consumption cost for performing thedelivery at the destination.

Clause 30: The method of clause 28 or 29, wherein the at least onepredefined consumption parameter comprises one or more of: an energyconsumption in the UAV to deliver the goods at the destination, a totalenergy consumption comprising the energy consumption in the UAV and anelevation energy consumption to vertically elevate the UAV to theselected altitude, a time period from a reference time point to arrivalof the UAV at the destination, or a monetary cost to deliver the goodsat the destination.

Clause 31: The method of any one of clauses 24-30, wherein the liftingarrangement is operated to vertically elevate a platform for carryingthe UAV.

Clause 32: The method of clause 31, wherein the lifting arrangement(202A, 202B, 207) is operated to vertically elevate the platform whilethe UAV is carried by the platform.

Clause 33: The method of clause 31 or 32, further comprising: operating,after the UAV has been launched, the lifting arrangement to lower theplatform from the selected altitude to a predefined altitude.

Clause 34: The method of any one of clauses 31-33, wherein saidoperating (222) the lifting arrangement comprises: operating a conveyordevice to lift the UAV onto the platform at least when the platform isvertically elevated.

Clause 35: The method of any one of clauses 24-34, wherein saidoperating (222) the lifting arrangement comprises: operating anextendable mechanical connection device.

Clause 36: The method of any one of clauses 24-33, wherein saidoperating (222) the lifting arrangement comprises: operating an aircraft(202B) that carries the UAV.

Clause 37: The method of any one of clauses 24-36, wherein saidoperating (222) the lifting arrangement comprises: operating a flowgenerator to generate a vertical air flow towards the UAV.

Clause 38: The method of any one of clauses 24-30, wherein saidoperating (222) the lifting arrangement comprises: supplying energy froma ground-based power source to the UAV over a power cable connected tothe UAV while the propulsion system of the UAV operates to verticallyelevate the UAV, and wherein said causing (223) the UAV to be launchedcomprises: releasing the power cable from the UAV.

Clause 39: The method of any one of clauses 24-38, wherein said causing(223) the UAV to be launched comprises: providing a launch signal to theUAV when the lifting arrangement has elevated the UAV to the selectedaltitude, the launch signal causing the UAV to launch for thedestination.

Clause 40: A computer-readable medium comprising computer instructions(1102A) which, when executed by a processing system (1101), cause theprocessing system (1101) to perform the method according to any one ofclauses 24-39.

4. Controlling a Group of UAVs for Delivery of Goods

This part of the disclosure relates to an improvement in the energyefficiency when delivering goods by UAVs.

One major challenge when operating a UAV on a mission for deliveryand/or pick-up of goods is to ensure that the UAV has a sufficient reachto complete its mission given the available power capacity of the UAVand/or to make the most efficient use of the available power capacity.Conventionally, the reach of a UAV-based delivery system may be extendedby special long-reach design of the UAVs, by air charging, or byhandover of goods between UAVs. Each of these measures will increasecost and/or complexity of the delivery system.

FIG. 25A illustrates an example delivery system comprising a fleet ofUAVs 1. The delivery system comprises a control system 301 which isconfigured to communicate with the UAVs 1 over a wireless network 302.The control system 301 may be configured to assign missions to the UAVs1 in the fleet, where a mission may comprise delivery and/or pick-up ofgoods 4 at one or more destinations, as well as other tasks that involvea relocation of an UAV such as taking pictures, making measurements,etc.

The energy efficiency of an individual UAV, or plural UAVs, may beimproved by operating UAVs to fly in groups or “swarms”. The UAVs in aswarm fly in the same direction and at the same travel speed. The UAVsmay be arranged into such a swarm for at least part of their respectivemission, for example as long as their respective destination is inapproximately the same direction. During flight, UAVs may leave and jointhe swarm.

Further, a swarm of UAVs may be broken up into smaller swarms, or swarmsmay be merged to form a larger swarm.

FIGS. 25B-25C show two non-limiting examples of swarm formations(“flight formations”) that may be attained by a group of UAVs 1. In FIG.25B, the swarm has a line formation, in which the UAVs 1 are arrangedone after the other in the flight direction DIR of the swarm. In FIG.25C, the swarm has a delta formation, in which the UAVs 1 are arrangedto form an arrow shape in the flight direction DIR. FIG. 25C may be inplan view or in elevated side view. The swarm formation need not betwo-dimensional, as shown, but may be three-dimensional.

Embodiments relate to the techniques for configuring a swarm of UAVs,and in particular the relative position of one or more UAVs in theswarm, to improve the performance of an individual UAV in the swarm, asubset of the UAVs in the swarm, or the swarm as a whole. The relativeposition of a UAV may be changed by changing the distance and/ordirection between the UAV and one or more other UAVs in the swarm,and/or by switching places between the UAV and another UAV in the swarm,and/or by changing the swarm formation.

FIG. 26 is a flow chart of an example method 310 for controlling a groupof UAVs, which are on one or more missions to deliver and/or pickupgoods and which travel in a common direction (cf. DIR in FIGS. 25A-25B)and thereby define a swarm. The example method 310 may be performed bythe control system 301 or, as will be described below with reference toFIGS. 31A-31C, by one or more of the UAVs in the swarm. Step 311 obtainsdrag data indicative of the air resistance for a set of UAVs in theswarm. Such a set of UAVs comprises one or more UAVs and is denoted“monitored set” in the following. As will be described further belowwith reference to FIGS. 29A-29C, the drag data may include a measuredvalue or a predefined value, or both. In some embodiments, step 311 maycalculate a parameter value that represents the air resistance, based onthe drag data. Step 312 determines a respective relative position foreach UAV in the monitored set, based on the drag data, or the parametervalue if calculated by step 311. In step 313, each UAV in the monitoredset is controlled to attain its relative position.

The forces acting on an example UAV is illustrated in FIG. 30A, wherethe main body of the UAV 1 comprises at least two rotors or otherspatially separated propulsion elements 6, which are operated togenerate a respective thrust force FT1, FT2. In order for the UAV 1 toremain at its altitude, the vertical components of the trust forces FT1,FT2 need to be equal to the gravitational force FW acting on the UAV 1.The gravitational force FW corresponds to the total weight of the UAV,including any payload carried by the UAV. In order for the UAV 1 to movein the flight direction DIR, the rotors 6 need to generate a horizontalcomponent of thrust force this direction. As seen, this may be achievedby increasing thrust force FT2 in relation to thrust force FT1, causingthe UAV 1 to tilt in the flight direction DIR. When the UAV 1 moves atconstant speed, the horizontal component of the total thrust force isequal to a force FD generated by air resistance, commonly denoted “dragforce” or “drag”. The drag force FW is a function of the size and shapeof the UAV 1, as well as the size and shape of the payload 4, if present(cf. FIG. 25A). The drag force FW is also a function of the currentabsolute travel speed of the UAV 1, as well as the current direction andabsolute speed of wind. As used herein, “absolute speed” is givenrelative to a fixed reference and may be ground speed. Further, as usedherein, “air speed” of an UAV refers to the sum between the absolutetravel speed of the UAV in the current direction and the absolute windspeed in the flight direction, where wind speed opposite to the flightdirection has a negative value.

It is realized that the drag force FD may have a significant impact onthe energy consumption of the UAV 1. A UAV carrying a payload with largecross-section and low weight may have the same total energy consumptionas an identical UAV carrying a payload with small cross-section and highweight. In the context of a swarm, the wind speed, and possibly also thewind direction, will depend on the position of the UAV relative to otherUAVs in the swarm. Thus, since the drag force FW is a function of windspeed/direction, one or more UAVs may be selectively re-positionedrelative to other UAVs in the swarm based on their actual or estimateddrag force. In one example, the above-mentioned UAV carrying a payloadwith large cross-section may be positioned to act as a “wind cover” forother UAVs in the swarm and thereby significantly reduce the energyconsumption of the other UAVs. In another example, the above-mentionedUAV carrying a payload with large cross-section will benefitsignificantly, in terms of energy consumption, from being positionedbehind one or more other UAVs that provide wind cover. It is thusrealized that significant improvements in terms of energy consumption,reach, flight time, etc. may be achieved by adjusting the relativeposition of one or more UAVs in a swarm based on estimated drag, forexample in accordance with the example method 310.

As indicated in FIG. 26, the determination in step 312 may be performedto achieve an efficiency objective. In some embodiments, step 312 mayinvolve optimizing the respective relative position of the UAV(s) in themonitored set to meet the efficiency objective. The efficiency objectivefor a swarm may change over time and may be set by the control system301 or by one or the UAVs in the swarm. In one example, the efficiencyobjective is set to minimize the air resistance for at least one UAV inthe swarm, which may or may not be included in the monitored set. Inanother example, the efficiency objective is set to minimize the energyconsumption for at least one UAV in the swarm. In a further example, theefficiency objective is set to minimize the flight time for at least oneUAV in the swarm, for example by allowing the speed of the swarm to beincreased or by allowing the at least one UAV to operate at an increasedspeed after leaving the swarm.

The example method 310 may include an optional step 311B of obtainingcurrent status data for the swarm, and step 312 may determine therespective relative position of the UAV(s) in the monitored set as afunction of the drag data and the current status data. For example, thecurrent status data may represent the number of UAVs in the swarm, theabsolute travel speed of the swarm, the total weight of one or moreUAVs, a remaining energy level in the local power source of one or moreUAVs (cf. 1010 in FIG. 1), a model identifier of one or more UAVs, thedestination of one or more UAVs, or any combination thereof. Byincluding the current status data in the determination by step 312, amore precise optimization of the swarm is possible.

A simplified example of such use of current status data is shown inFIGS. 27A-27B. In FIG. 27A, an UAV 1 that carries a large-sized payload4 and has a large remaining energy level, indicated by icon 315, isarranged at the front of the swarm to act as a wind cover for the otherUAVs. In FIG. 27B, the UAV 1 carrying the large-size payload 4 is low inenergy, as indicated by icon 315, and is therefore arranged at thetrailing end of the swarm to benefit from the wind cover provided by theother UAVs 1.

In some embodiments, steps 312 and 313, and optionally step 311 and/orstep 311B, may be performed continuously or intermittently for theswarm. This enables the swarm to account for changes in externalconditions such as wind speed/direction, changes caused by one or moreUAVs joining and/or leaving the swarm, as well as changes in theabove-mentioned current status data for the swarm.

FIG. 28 is a flow chart of an example procedure 320 for arranging theUAVs in swarm. The example procedure 320 may be performed intermittentlyduring swarm travel, for example at initial formation of a swarm andwhenever a major structural change of the swarm occurs, for example whenthe number of UAVs in the swarm is changed. In step 321, a flightformation for the swarm is determined. In some embodiments, the flightformation is determined to minimize the air resistance of the swarm as awhole in view of the wind direction at the location of the swarm.Alternatively or additionally, the flight formation may be determinedbased on the air speed at one or more UAVs. Alternatively oradditionally, the flight formation may be determined based on the numberof UAVs in the swarm. Generally, the flight formation may be determinedbased on the drag data, the current status data, or any combinationthereof. In some embodiments, the flight formation is selected among aset of predefined flight formations, for example including a lineformation (FIG. 25B) and one or more arrow formations (FIG. 25C). In anon-limiting example, step 321 may select a line formation if the swarmencounters a strong headwind, and an arrow formation is the swarmencounters a strong crosswind.

In some embodiments, the predefined flight formations are associatedwith a respective flight template, which may comprise a predefinedspatial arrangement of relative positions (“slots”), where each suchslot is designated for one UAV. In some embodiments, the flight templatemay also associate an efficiency rank with the respective slot. Theefficiency rank is a relative parameter that ranks the slots by airresistance for a nominal case, for example assuming that all UAVs areidentical and carry no payload. A high efficiency rank may imply a lowair resistance. For example, slots at the front of a flight formationare likely to have low efficiency rank. Reverting to FIG. 28, step 322may obtain the flight template for the flight formation selected by step321 and the associated efficiency ranks. Step 323 may obtain travelcapacity data of one or more UAVs. For the respective UAV, the travelcapacity data may include an estimation of a remaining flight range. Insome embodiments, the remaining flight range may represent the flightdistance (or equivalently, flight time) that remains before the localpower source in the UAV is empty or has reached a low energy limit. Inthe following, the remaining flight range is designated ERFD (“estimatedremaining flight distance”). The ERFD may be continuously orintermittently calculated by or for the respective UAV, for examplebased on historic or current power consumption and current energy levelof the local power source. The historic or current power consumption maybe supplemented or replaced by calculations based on drag data andstatus data, such as total frontal area, total weight, air speed, etc.It may be noted that ERFD, irrespective of calculation, is a compositeparameter that inherently includes both drag data and status data of anUAV. Specifically, momentary changes in ERFD for an UAV during flight ina swarm is directly proportional to changes in air resistance, since allother variables affecting the ERFD may be considered to be constant. Instep 324, the UAVs are assigned to the slots so as to match the ERFD tothe efficiency ranks of the slots. For example, the matching may involveassigning UAVs with higher ERFD to slots with lower efficiency rank.

It should be understood that other definitions of the remaining flightrange are possible. In one example, the remaining flight range mayrepresent the flight distance (or equivalently, flight time) thatremains until the UAV has completed its mission, for example by arrivingat its destination to perform a pick-up/delivery of goods. Such aremaining flight range may be used to optimize the monitored set toenable the respective included UAV to complete its mission.

The procedure 320 results in a basic swarm configuration, which isoptimized for flight distance or flight time based on a genericestimation of air resistance for the respective UAV. By applying thisbasic swarm configuration to the swarm, the magnitude and number ofchanges among the UAVs in the swarm during continued flight, for examplebased on the method 310, will be reduced. This will in turn reduce thecomplexity of controlling the UAVs during flight in the swarm.

In other embodiments, the efficiency rank and the travel capacity datamay be omitted and step 324 assigns the UAVs to the slots based on someother logic or randomly.

Reverting to step 311 in FIG. 26, the drag data may comprise apredefined value for the respective UAV in the measured set. Thepredefined value may be a pre-estimated air resistance value (“dragvalue”) for the UAV 1 and any payload 4 it presently carries. Forexample, the UAVs may be categorized into different UAV types by airresistance and the payloads 4 may be categorized into different payloadtypes by air resistance. Thus, based on

UAV type and payload type, a drag value may be estimated for therespective UAV.

FIG. 29A is a flowchart of an example procedure for determining a dragvalue for an UAV based on drag data comprising one or more predefinedvalues. As indicated, the example procedure may be part of step 311.Step 331 obtains an identifier (“goods ID”) for the payload carried bythe UAV. The goods ID may directly or indirectly represent theabove-mentioned payload type. The goods ID may be obtained from ascheduling device in the delivery system, or may be read by the UAV fromthe payload, for example by the above-mentioned code reader (cf. 1020 inFIG. 1). Step 332 determines, based on the goods ID, the frontal area ofthe UAV combined with its payload. Step 332 may be performed by use of alook-up table or algorithmically. It may be noted that the frontal areamay be supplemented by data on the 2D or 3D shape of the payload 4,and/or other aerodynamic properties of the payload. Step 333 estimatesthe air speed of the UAV. The air speed may be given by the absolutetravel speed of the UAV (and thus the swarm) and an estimation of thewind speed and wind direction. The wind speed and wind direction may begiven by a weather forecast for the location of the swarm, optionallymodified based on the slot occupied by the UAV.

Alternatively or additionally, the wind speed/direction may be wind datacompiled based on wind measurements performed by a large number of UAVs,which may be included in the fleet or not. Such UAVs may continuouslymeasure and report local wind speeds and directions together with 3Dcoordinates to a wind server, which is configured to compile thereported data into a wind map, for example a 3D array layering above ageographical map.

The wind server may also generate wind maps for a region withinsufficient amounts of reported data by use of learning model, forexample a convolutional neural network, which is trained based oncompiled wind maps for different regions together with 3D models of theregions, and regional wind and weather conditions, etc. The wind servermay then use the trained learning model to estimate wind maps for anyregion based on a 3D model of the region and regional wind and weatherconditions. Such a wind server may be queried to obtain wind data in anyof the concepts, aspects and embodiments described herein. Given thefrontal area of the payload and the estimated air speed, and assumingthat at least the frontal area of the UAV is known, step 334 maydetermine the drag value of the UAV.

In step 311, the drag data may comprise a measured value by or for theUAV, in addition to or instead of the predefined value. In the exampleprocedure of FIG. 29A, step 333 may estimate the air speed of the UAV byobtaining measurement data from a wind sensor on the UAV, or on anotherUAV in the swarm.

FIG. 29B is a flowchart of another example procedure for determining adrag value for a UAV based on a measured value. As indicated, theexample procedure may be part of step 311. Assuming that the UAVcomprises two or more spatially separated propulsion elements (cf.rotors 6 in FIG. 30A), step 341 measures the distribution of propulsionenergy between the propulsion elements, and step 343 calculates thecurrent air resistance based on the distribution. As understood from thedescription of FIG. 30A, the difference in propulsion energy betweenrotors 6 represent the energy spent on compensating for air resistance.Step 341 may be performed when the acceleration is zero or close tozero. Alternatively, the procedure may include a step 342 of measuringthe acceleration, and step 343 may compensate for the measuredacceleration when calculating the air resistance.

FIG. 29C is a flowchart of a further example procedure, which may bepart of step 311.

Step 351 measures the orientation of the UAV in relation to a referenceplane. FIG. 30B shows an example of such a measurement, where theorientation is given by the tilt of the UAV 1 in the flight directionDIR, for example represented by an angle θ between a reference directionRD of the UAV 1 and a vertical reference plane RP facing DIR. Generally,the orientation may be represented by more than one angle, for exampleconventional angles for pitch and roll of the UAV, as measured by one ormore sensors on the UAV (cf. 1016 in FIG. 1). Step 353 calculates thecurrent air resistance based on the orientation, when the accelerationis zero or close to zero or by accounting for the current accelerationmeasured by step 352.

In some embodiments, the methods and procedures described in theforegoing are performed by the control system 301 in FIG. 25A. Withreference to the method 310 in FIG. 26, the control system 301 mayobtain (step 311) drag data and optionally status data (step 311B) forthe respective UAV in the monitored set, and transmit (step 313) controldata to the swarm causing the respective UAV to attain its relativeposition, as determined by the control system 301 (step 312). Asunderstood from the foregoing, the control system 301 may or may notcommunicate with the swarm to obtain the drag data.

In some embodiments, at least part of the methods and procedures areperformed by the respective UAV in the monitored set. For example, oneor more of the procedures in FIGS. 29A-29C may be performed by therespective UAV and the resulting drag value may be transmitted to thecontrol system 301.

In some embodiments, the methods and procedures are performed by atleast one of the UAVs in the swarm. For example, at least part of themethods and procedures may be performed by a master UAV among the UAVsin the swarm. The master UAV may thus take the role of the controlsystem 301 and is configured to at least communicate control data to theUAVs in the swarm. The master UAV may also be configured to receive UAVdata from the UAVs, for example drag data and/or status data. FIGS.31A-31B show two examples of communication paths within the swarm. InFIG. 31A, the master UAV 1M communicates directly with the other UAVs inthe swarm. In FIG. 31B, the UAVs are configured to form a sequence ofcommunication links between pairs of UAVs, where the respective UAV maytransfer at least part of incoming data to another UAV.

In some embodiments, the master UAV is dynamically selected among theUAVs in the swarm, for example by performing a voting procedure amongthe UAVs. The voting procedure may be based on any conventionalalgorithm for leader election, for example as practiced in meshnetworks. The voting procedure may be performed at initial formation ofthe swarm and/or in advance of the master UAV leaving the swarm.

In other embodiments, the master UAV is pre-selected, for example by thecontrol system 301. The master UAV may be a UAV that is known to beincluded in the swarm from start to a final destination.

In some embodiments, the method and procedures are performed jointly bythe UAVs in the swarm, and the UAVs are operated to pairwise switchplaces in the swarm based on UAV data exchanged between the UAVs. Anexample is shown in FIG. 31C, in which two UAVs 1 exchange UAV data, asindicated by a dashed arrow, and then switch places, as indicated by asolid arrow 360. It should be understood that the UAV data may beexchanged between pairs of UAVs in other ways, for example via one ormore other UAVs in the swarm. The UAV data may comprise drag data, andoptionally status data. In some embodiments, the UAV data may comprisethe travel capacity data, which may be given by the above-mentionedremaining flight range. In the following, use of the travel capacitydata will be exemplified for the ERFD. The description is equallyapplicable to other definitions of the travel capacity data.

In some embodiments, the UAV data may be used to update a swarm that isconfigured in accordance with a flight template associated withefficiency ranks. In one example, a switching of positions is decidedbased on the ERFD of the respective UAV and the efficiency rank of theslot currently occupied by the respective UAV. The decision may made bypairs of UAVs, by a master UAV, or by the control system 301. Theswitching may be made to maximize the difference between the ERFD andthe efficiency rank in the respective slot. Thus, UAVs switch places ifone of the UAVs has both a higher ERFD and a higher efficiency rank thanthe other UAV. In other words, a switching will be performed if thetotal ERFD for the pair of UAVs is deemed to become higher when the UAVsswitch places. When such switching is performed throughout the swarm,the UAVs with the highest ERFD will be in positions that take most airresistance, while UAVs with lower ERFD will fly in cover. The result isincreased efficiency and thereby longer overall flight distance for theswarm. Additional information may be exchanged and used to decide onswitching. For example, the additional information may include plannedflight distance for the respective UAV, enabling the switching tooptimize the swarm to ensure that all UAVs are capable of completingtheir planned flight distance. It should be noted that the ERFDdecreases for the respective UAV during flight, and it may therefore bebeneficial for the UAVs to repeatedly exchange UAV data and decide onswitching.

The switching based on exchange of UAV data may be applied to achieveother efficiency objects. For example, the switching may be decided tomaximize the ERFD for one or more selected UAVs in the swarm, causingthe selected UAV(s) to be placed in the slots with the highestefficiency ranks.

Reverting the example method 310 in FIG. 26, step 312 may also accountfor upcoming events when determining the relative position of therespective UAV in the monitored set. In some embodiments, the relativeposition is determined as a function of a predicted time point when atleast one UAV leaves the swarm, as indicated by 1L in FIG. 32, and/or apredicted time point when at least one UAV arrives and joins the swarm,as indicated by 1A in FIG. 32. For example, the UAV 1L and/or other UAVsin the swarm may be re-positioned to facilitate for the UAV 1L to leavethe swarm. Similarly, the UAVs in the swarm may be re-positioned toprovide a suitable position for the joining UAV 1A in the swarm, forexample based on its ERFD.

In the following, clauses are recited to summarize some aspects andembodiments as disclosed in the foregoing.

Clause 1: A method of controlling unmanned aerial vehicles, UAVs (1),which are organized in a group to perform one or more missions todeliver and/or pick up goods (4), said method comprising:

-   -   obtaining (311) drag data indicative of air resistance for one        or more UAVs in the group;

determining (312), as a function of the drag data, a respective relativeposition of at least the one or more UAVs within the group; and

controlling (313) at least the one or more UAVs to attain the respectiverelative position.

Clause 2: The method of clause 1, wherein the drag data comprises atleast one of a predefined value for the one or more UAVs, or a measuredvalue by or for the one or more UAVs.

Clause 3: The method of clause 2, wherein the predefined value isobtained as a function of the goods (4) carried by the one or more UAVs(1).

Clause 4: The method of clause 2 or 3, wherein the predefined value isindicative of a frontal area of the one or more UAVs (1) when carryingits goods (4).

Clause 5: The method of any one of clauses 2-4, wherein the measuredvalue is at least one of a travel speed of the one or more UAVs, an airspeed at the one or more UAVs, a wind speed and/or wind direction, anacceleration of the one or more UAVs, an orientation of the one or moreUAVs in relation to a reference plane (RP), or a distribution ofpropulsion energy to spatially separate propulsion elements (6) on theone or more UAVs.

Clause 6: The method of any preceding clause, wherein said determining(312) the respective relative position and said controlling (313) areperformed continuously or intermittently while the UAVs (1) areorganized in the group.

Clause 7: The method of any preceding clause, further comprising:obtaining (311B) current status data for the group, wherein therespective relative position is determined as a function of the dragdata and the current status data, and wherein the current status datacomprises one or more of: a total weight of a respective UAV, a count ofthe UAVs in the group, a speed of a respective UAV, a remaining energylevel in a power source (1010) of a respective UAV, a model identifierof a respective UAV, or a destination of a respective UAV.

Clause 8: The method of any preceding clause, wherein said determining(312) the respective relative position comprises: optimizing, as afunction of the drag data, the respective relative position of at leastthe one or more UAVs within the group to meet an efficiency objective.

Clause 9: The method of clause 8, wherein the efficiency objectivecomprises:

-   -   minimizing, for at least one UAV in the group, one or more of        air resistance, energy consumption or flight time.

Clause 10: The method of any preceding clause, further comprising:determining (321, 322) a flight formation for the group.

Clause 11: The method of clause 10, wherein the flight formation isselected among a set of predefined flight formations.

Clause 12: The method of clause 10 or 11, wherein the flight formationis associated with a template of predefined positions, wherein saidmethod further comprises: selectively assigning (324) at least the oneor more UAVs to at least a subset of the predefined positions.

Clause 13: The method of clause 12, further comprising: obtaining (323)travel capacity data of at least the one or more UAVs, wherein thepredefined positions have a respective efficiency rank, and wherein atleast the one or more UAVs are selectively assigned to the predefinedpositions to match the travel capacity data to the efficiency ranks ofsaid at least a subset of the predefined positions.

Clause 14: The method of any one of clauses 1-12, wherein said obtaining(311) the drag data comprising: obtaining travel capacity data of atleast the one or more UAVs, wherein the respective relative position isdetermined as a function of the travel capacity data.

Clause 15: The method of clause 14, further comprising: repeatedlyupdating the travel capacity data, wherein said determining (312) therespective relative position and said controlling (313) comprise:selectively causing one or more pairs of UAVs to switch places in thegroup based on the updated travel capacity data.

Clause 16: The method of clause 14 or 15, wherein said obtaining (311)the drag data comprises: causing each UAV among the one or more UAVs todetermine its travel capacity data, and causing the one or more UAVs toexchange the travel capacity data.

Clause 17: The method of any one of clauses 13-16, wherein the travelcapacity data is indicative of a remaining flight range of the one ormore UAVs at a defined time point.

Clause 18: The method of any one of clauses 1-16, wherein said obtaining(311) the drag data, said determining (312) the respective relativeposition, and said controlling (313) are performed by a master UAV (1M)in the group.

Clause 19: The method of any preceding clause, wherein the respectiverelative position is further determined as a function of a predictedtime point of at least one UAV (1A, 1L) leaving or joining the group.

Clause 20: A control system configured to perform the method of any oneof clauses 1-19 and comprising a communication device (1103) forcommunicating with at least one UAV in the group.

Clause 21: An unmanned aerial vehicle, UAV, which is configured to beorganized in a group with at least one further UAV and to perform themethod of any one of clauses 1-19, said UAV comprising a communicationdevice (1013) for communicating with said at least one further UAV.

Clause 22: A computer-readable medium comprising computer instructions(1102A) which, when executed by a processing system (1101), cause theprocessing system (1101) to perform the method of any one of clauses1-19.

5. Configuring a System for Delivery of Goods by UAVs

This part of the disclosure relates to a technique for configuring adelivery system to improve its resource efficiency and/or flexibility.

One problem that occurs in systems for delivery of goods by UAVs is thatthe recipient might not be present to receive the goods. Often, it isnot an option to leave the goods at the location of the recipient, forexample outside a house. Conventionally, deliveries need to be plannedso that the UAVs have sufficient energy to return with the goods to itsorigin, for example a warehouse. In addition, delivery by UAVs involvesa complex route/resource planning problem to optimize the utilization ofthe fleet of UAVs.

This part of the disclosure is based on the insight that utilization andflexibility may be improved by introducing mobile storages, also denoted“mobile nests” herein, which may be used as an intermediate storagefacility where goods may be stored for a shorter period of time. Theintroduction of mobile nests provides for better resource efficiency,since the mobile bests may be positioned to facilitate operation of thedelivery system. For example, UAVs may return goods to the mobile nestsinstead of to the warehouse and perform another delivery, allowing thefinal delivery of the goods to be performed by the UAV or another UAV ata later time. Further, the provision of nests may extend the distancefor UAV-based delivery of goods, since one UAV may transport goods to anest and another UAV may pick up the goods for transportation to arecipient or another nest. The nests may also be used as a switchingpoints between different delivery systems, for example for hand overgoods from one provider to another.

FIGS. 33A-33C illustrate an example delivery system configured inaccordance with an embodiment. The delivery system comprises one or morecentral storage facilities 400 (one shown), for example a warehouse, andone or more local storage facilities (“fixed nests”) 401 (one shown).The storage facilities 400, 401 are stationary and thus have fixedlocations 400′, 401′ in a common coordinate system, for example given by(x,y,z) coordinates as shown. The delivery system further comprisesmobile nests 402 (one shown) with variable positions in the commoncoordinate system. Generally, the delivery system may be seen tocomprise “first storages” 400, 401 with fixed positions, and “secondstorages” 402 with variable positions. The delivery system may alsocomprise a fleet of UAVs 1.

FIG. 34A is a flowchart of an example method 410 for transportation ofgoods (“items”) in this type of delivery system. In this example, it isassumed that the items 4 to be delivered are located at a warehouse 400at the onset of the method 410, as shown in FIG. 33A. In step 411, oneor more mobile nests 402 are moved into a respective selected restposition 402′ (FIG. 33A). In step 412, items that have been ordered fordelivery is transported at one or more time points from the warehouse400 to the fixed nests 401 and the mobile nests 402, as shown in FIG.33B. Any suitable vehicle 405 may be used for this transport, forexample trucks, vans (as shown), cars, ships, UAVs, etc. In step 413,the items 4 are delivered to the recipients by UAVs 1 from the fixednests 401 and the mobile nests 402, and possibly from the warehouse 400,as shown in FIG. 33C. It is realized that the rest position 402′ of therespective mobile nest 402 may be adapted to achieve various objectivessuch as increasing the capacity of the delivery system, extending therange of the delivery system, reducing energy consumption, increasingflexibility, etc.

In the example method 410, the one or more mobile nests 402 are firstcontrolled to move to the respective rest position 402′, and the itemsto be delivered are then transported to mobile nest(s) 402 in the restposition(s) 402′, and to the fixed nests 401. The mobile nests 402 maythus be distributed well in advance, for example based on estimated needfor capacity. The estimation may be done on historical data and/or byuse of preliminary requests for deliveries or pick-ups by users of thedelivery system. One advantage of the time separation between nestdistribution and goods distribution is that the goods may be deliveredto the nests during bad conditions like major incidents, disasters ortraffic congestions. For example, if goods are transported by cargodrones from the warehouse 400 to the nests 401, 402, the goods may beefficiently delivered to the nests 401, 402 even if there are trafficcongestions for example during rush hours. In high risk areas fordisasters, for example earthquake zones or a quarantined area, mobilenests 402 may be distributed and used as intermediate storages to enableUAV-based delivery of supplies and medicine to areas that arecomplicated or risky to reach by ground transportation.

In an alternative to the example method 410, at least some of the itemsto be delivered are transported by the mobile nest(s) 402 to the restposition(s) 402′.

The fixed and mobile nests 401, 402 may be used for intermediate storageof an item in the vicinity of its final delivery point, at which it willbe received/retrieved by the consignee. For example, the nests 401, 402may be placed in locations that are unused, for example on the roof of abuilding or on an unused parking space.

The items may be transported to the nests 401, 402 using the bestdelivery method based on, for example, one or more of: distance, weightof the items, number of items, value of the items, urgency, cost, speedof delivery, and available resources for the transportation, includingvehicles and staff.

The nest 401, 402 may be configured to ensure tamper resistant storageof items, both for items delivered by the vehicles 105 and items thatmay be dropped off by a UAV for intermediate storage. Tamper resistancemay be provided by a physical barrier or by a monitoring system thatalerts an operator of unauthorized access. The nest may also comprise acharging station that allows one or more UAVs to land and re-chargetheir local power source (cf. 1010 in FIG. 1).

In some embodiments, a nest 401, 402 may be used for an intermediatestorage of an item until one of the following events occurs: thedelivery system detects that the consignee (for example, a recipient) isready to receive the items, an UAV on the nest 401, 402 is re-chargedand operable to deliver the item, or a new UAV arrive at the nest 401,402 to continue the delivery of the item.

In some embodiments, once the item is stored in a nest 401, 402 locatedwithin range of the final delivery point, the consignee may be notifiedabout the item and is allowed to schedule delivery, subject to theavailability of UAVs for performing the final delivery.

In the following, embodiments for determining the rest position of therespective mobile nest 402 (“second storage”) will be described. Forclarity of presentation, these embodiments are exemplified for deliveryof items to delivery points, which may represent a final delivery pointselected by a consignee for the delivery or the location of anotherfirst or second storage in the delivery system. However, it may be notedthat the embodiments are equally applicable to pick-up of items atpick-up points, which may represent the location selected by a consignor(for example, a user wanting a parcel collected) for the pick-up or thelocation of another first or second storage in the delivery system.Generally, the delivery and pick-up points are “destination points” forthe UAVs irrespective of the direction that items are transported by theUAVs in relation to first and second storages.

The second storages 402 may be road-based vehicles, as shown in FIGS.33A-33C. Generally, a second storage 402 is any storage facility thatmay be freely positioned and re-positioned at any rest position withinthe common coordinate system. Thus, the second storage 402 may be acontainer that is lifted off or a trailer that is disconnected from aroad-based vehicle at a selected rest position, and which is laterretrieved by this or another road-based vehicle. The first storages 400,401 may be any storage facility that cannot be freely positioned and hasa predefined location, at least at one or more predefined time points.Thus, the respective first storage may be any type of permanentstructure such as a building, or a structure located on a vehicle thatwith restricted movement such as a train or a bus. For example, a firststorage may be formed by a stop of the train or bus at a predefined timepoint. Generally, the first storages 400, 401 are associated with firstpositions that are known to the delivery system at any given time point.

FIG. 34B is a flow chart of an example method 420 for configuring adelivery system comprising the above-mentioned first and secondstorages. Step 421 obtains position data for a plurality of deliverypoints to which items are to be delivered. Step 422 operates aclustering algorithm of the position data to determine clusters ofdelivery points. Any density-based or partitional clustering algorithmmay be used. In some embodiments, the clustering algorithm may beconfigured to separate the delivery points into any number of clustersgiven by the clustering itself. In other embodiments, the number ofclusters may be predefined for the clustering algorithm. In someembodiments, such a predefined number of clusters may be set in relationto the number of currently available second storages. Step 423 evaluatesthe clusters in relation to the first positions of the first storages todetermine a set of rest positions (“stopping positions”) for at leastone second storage.

The method 420 provides a technique of adapting the capacity of thedelivery system to a current demand for delivery of goods in a resourceefficient way, by accounting for the first positions of the firststorages when determining the set of rest positions for the secondstorage(s).

In some embodiments, the set of rest positions is determined based on anevaluation function that evaluates the resource efficiency of assigninga respective destination point in a cluster to a reference point of thecluster in relation to assigning the respective destination point to oneof the first positions. Such an evaluation function may evaluate theresource efficiency in terms of energy consumption, travel distance,delivery time, etc.

FIG. 35A shows an example delivery system with six first storages 400,401 made up of one warehouse 400 and five fixed nests 401 that aredistributed in a region around the warehouse 400. The delivery systemalso comprises four second storages 402, which are stationed at thewarehouse 400 when not in use. Black dots represent the plurality ofdelivery points 403 to which items are to be delivered by UAVs. FIG. 35Aalso illustrates four clusters C1-C4 that have been generated by step422. It is realized that step 423 may be performed in different ways toevaluate the clusters C1-C4 in relation to the first storages 400, 401for determination of rest position(s). Some non-limiting examples willbe given below with reference to FIGS. 34C-34D and FIGS. 35B-35E.

Reverting to FIG. 34B, the example method 420 may comprise a step 424 ofassigning one or more of the first storages 400, 401 to a respectivefirst subset of the delivery points and assigning one or more restpositions of the second storages 402 to a respective second subset ofthe delivery points. All first and second subsets may be mutuallyexclusive. In this context, “assigning” infers that the first/secondstorage is associated with the delivery point(s) of the respectivefirst/second subset and will be used as a starting point for delivery ofgoods to the delivery point(s) by one or more UAVs. The example method420 may further comprise a step 425 of assigning UAVs 1 for performingthe delivery of goods from the respective first storage 400, 401 to itsassociated delivery points 403 and from the respective rest position ofthe second storage(s) 402 to its associated delivery points 403. Basedon the assignment by step 424, items may be transported by the vehicles105 to one or more second storages 402 at the rest position(s)determined by step 423. Based on the assignment by step 425, UAVs in thefleet of UAVs may be scheduled to perform the respective delivery. Someof the UAVs may be transported to the second storage(s) 402 togetherwith the items. Other UAVs may be scheduled to fly to the rest positionat a specific time point to perform one or more deliveries.

FIG. 34C is a flow chart of an example procedure for evaluating theclusters generated by the clustering in step 422. As indicated, theexample procedure may be part of step 423. Step 430 determines a costvalue for performing the delivery to each delivery point. The cost valueis determined by assuming that the delivery is performed via a referencepoint of the cluster to which the delivery point belongs. In FIG. 35A,the reference point is represented as C1′-C4′ in the clusters C1-C4. Thereference point may be set at or near a center point of the cluster. Thecenter point may be calculated in relation to the included deliverypoints, for example as a mean of their locations. The cost value for adelivery thus accounts at least for the UAV transportation of items fromthe reference point C1′-C4′ to the delivery point 403, as indicated byarrows in FIG. 35A. The cost value may also account for the transport ofitems and/or a second station 402 to the reference point C1′-C4′, forexample from the central warehouse 400, and/or the transport of UAVs 1to the respective reference point C1′-C4′. The cost value need not be amonetary value but may be given in any type of unit. In someembodiments, the cost value may be calculated as a function of distancein the common coordinate system and/or as a function of estimated energyconsumption. In this context, as least when relating to transport byroad, the distance may be determined to account for the availability ofroads and speed limits of these roads, for example to meet a time limitfor arrival at the respective reference point C1′-C4′. The cost valuemay also be calculated to account for “overall costs”, such as costs fordrivers of the second storages, parking fees for the second storages,etc. Such overall costs may be specific to each cluster and may be splitacross all delivery points associated with the cluster.

The procedure may then use the cost values to determine rest position(s)of second storages 402, as well as first storages 400, 401, to be usedfor the delivery of goods. In some situations, this determination mayresult in only first storages 400, 401 or only second storages 402 beingused. In the example of FIG. 34C, the determination involves a step 431of identifying and selecting, based on the cost values, delivery pointsthat are unsuitable for delivery via second storages 402 or,equivalently, delivery points that are more suitable for delivery viafirst storages 400, 401. For example, step 431 may select all deliverypoints with a cost value that exceeds a cost threshold, CTH. Theseselected delivery points are denoted “first storage delivery points”(FSDP) in the following. The CTH may be set to represent a nominal costfor performing a delivery via one of the first storages 400, 401. It isconceivable that the CTH is specific to each cluster C1-C4, or even toeach delivery point. In one embodiment, to set a CTH for each deliverypoint, step 431 may determine “candidate cost values” for delivery tothe delivery point via each one of the first storages 400, 401, and setthe CTH as a function of the candidate cost values. For example, the CTHmay be set is relation to the smallest of the candidate cost values.Thereby, step 431 will identify all delivery points for which it is morecost-effective to deliver the items via a first storage 400, 401.

Step 432 then determines a set of remaining clusters among the clustersafter removing the FSDP from the clusters, where each such remainingcluster includes at least one delivery point. Step 433 then determinesthe rest position(s) as a function of the remaining cluster(s), forexample by setting a rest position at the reference point of therespective remaining cluster. The effect of steps 431-433 may be seen bycomparing FIG. 35A with FIG. 35B, which illustrates the remainingclusters C2, C3 after removal of the FSDP from the clusters C1-C4 inFIG. 35A. The rest positions may be given by the reference points C2′,C3′ of the remaining clusters C2, C3. It should be noted that thereference points C2′, C3′ differ between FIG. 35A and FIG. 35B, sincethe included delivery points have changed.

Step 433 may further comprise assigning the FSDP among the firststorages 400, 401 according to any suitable algorithm. It is alsoconceivable that step 433 performs further refinement of the remainingclusters before determining the rest positions. FIG. 34C is a flowchartof an example procedure for assigning the FSDP in accordance with anembodiment. As indicated, the example procedure may be part of step 433.

In step 434, the respective delivery point in FSDP is associated withits closest first storage. The effect of step 434 is visualized in FIG.35C, where arrows from first storages 400, 401 to delivery points (blackdots) represent the resulting associations.

In step 435, the first storages 400, 401 are evaluated based on a costcriterion. In one example, step 435 may evaluate the first storages 400,401 for detection of a negative cost balance. Such a negative costbalance may be identified if the cost for performing deliveries via thefirst storage 400, 401 to its associated delivery points exceeds a costlimit. The cost limit may represent the setup costs for the firststorage 400, 401, or any other limit. Step 435 may also perform acorresponding evaluation of the second storages 402 as located at thereference points C2′, C3′ of the remaining clusters C2, C3. Step 435 maythus result in a set of first and/or second storages 400, 401, 402 withnegative cost balance, denoted “candidate storage set” (CSS) in thefollowing.

Step 436 operates a further clustering algorithm on the locations of thestorages in the CSS. The further clustering algorithm may be adensity-based algorithm such as DBSCAN, OPTICS, mean-shift, etc. Step436 results in one or more storage clusters. The effect of step 436 isvisualized in FIG. 35D, where two subsets of the first storages 401 areincluded in a respective storage cluster N1, N2. In FIG. 35D, thewarehouse 400, the fixed nest 401 at the top, and the second storages atthe reference points C2′, C3′ are not included in the candidate storageset and have thus not been found to have a negative cost balance in step435. These storages will keep their assigned delivery points, given bysteps 432-433 for second storages 402 (cf. FIG. 35B) and step 434 forfirst storages 400, 401 (cf. FIG. 35C).

In step 437, one storage is selected per storage cluster N1, N2,resulting in a “selected storage” (SS) or, equivalently, “selectedstorage position”. In some embodiments, step 437 excludes any secondstorages, if present, and selects the SS among first storage(s) in therespective storage cluster. In some embodiments, step 437 determines acenter point of the respective storage cluster, determines the distancefrom each storage in the storage cluster to the center point, andselects the SS as a function of the distances. In some embodiments, theSS may be selected as function of the distances and the number ofdelivery points associated with each storage in the storage cluster. Forexample, the distance of each storage may be downscaled by its number ofassociated delivery points. In FIG. 35D, center points of the storageclusters N1, N2 are designated by N1′, N2′.

In step 438, all delivery points that are associated with the storagesin the respective storage cluster are assigned to the SS for the storagecluster. The effect of step 438 is visualized in FIG. 35D, where thedelivery points designated by arrows 401X have been added to theselected storages of the storage clusters N1, N2 (FIG. 35D).

Finally, in step 439, the rest position(s) for the second storages maybe updated, if steps 435-437 has changed the content of delivery pointsin the remaining cluster(s). The updated rest position may be set inrelation to the center point of respective remaining cluster. In theexample of FIG. 35D, step 439 need not be performed.

FIG. 35E illustrates the resulting configuration of the delivery systemafter completion of step 439. It is understood that the method 420,irrespective of embodiment, determines first locations 401′ of firststorages to be used for delivery to a respective subset of deliverypoints, as well as second locations (rest positions) to be attained bysecond storages for delivery to a respective subset of delivery points.

The methods and procedures described above with reference to FIGS. 34-35may be performed by a control system in the delivery system. FIG. 36shows an example of such a control system 440, which comprises acalculation module 441 and a distribution module 442. The calculationmodule 441 may perform the method 420 in FIG. 34B, optionally based onthe embodiments in FIG. 34C and/or FIG. 34D, to calculate a set of firstpositions [401′] and a set of second positions [402′] to be used fordelivery of goods to a plurality of delivery points. The delivery points[403] are provided as input to the calculation module 441. The input tothe calculation module 441 may further comprise, as shown, the number ofsecond storages 402 that are available to be used (#M), the positions ofall first storages 400, 401 that are available to be used (FP), orpredefined cost parameters that may be used in the calculations (CD),such as the above-mentioned overall costs, predefined thresholds orlimits (if used), etc. The distribution module 442 may be configured toreceive the sets of first and second positions [401], [402] and tocommunicate corresponding configuration data to the second storages 402,UAVs 1 and transportation vehicles 405. The distribution module 442 maythereby perform the transportation method 410 in FIG. 34A by providingthe configuration data to the second storages 402 in step 411, to thetransportation vehicles 405 in step 412 and to the UAVs 1 in step 413.

In the following, clauses are recited to summarize some aspects andembodiments as disclosed in the foregoing.

Clause 1: A method of configuring a delivery system, said deliverysystem comprising first storages (400, 401) with predefined positions,second storages (402) with variable positions, and unmanned aerialvehicles (1), UAVs, which are operable to transport goods betweendestination points (403) and the first and second storages (400-402),the destination points being locations where the UAVs pick up or deliversaid goods, said method comprising:

obtaining (421) position data for the destination points;

operating (422) a clustering algorithm on the position data to determineclusters (C1-C4) of destination points; and

evaluating (423) the clusters in relation to the predefined positions ofthe first storages to determine a set of stopping positions (402′) forat least one of the second storages (402).

Clause 2. The method of clause 1, wherein the set of stopping positions(402′) is determined by evaluating the resource efficiency of assigningthe destination points to reference points (C1′-C4′) in the clusters(C1-C4) in relation to assigning the destination points to the firststorages (400, 401).

Clause 3. The method of clause 1 or 2, further comprising: associating(424) one or more of the first storages (400, 401) to a respective firstsubset of the destination points; and associating (424) each stoppingposition in the set of stopping positions (402′) to a respective secondsubset of the destination points.

Clause 4. The method of clause 3, further comprising: assigning (425)subsets of the UAVs (1) for delivery from the one or more of the firststorages (400, 401) to the respective first subset of the destinationpoints and from said each stopping position to the respective secondsubset of the destination points.

Clause 5. The method of any preceding clause, wherein said evaluating(423) comprises: determining (430), for a respective destination pointin a respective cluster, a cost value for transportation to or from therespective destination point via a reference position (C1′-C4′) withinthe respective cluster, wherein the set of stopping positions (402′) isdetermined as a function of the cost value.

Clause 6. The method of clause 5, wherein said evaluating (423) furthercomprises: identifying (431), among the destination points, a selectedset of destination points for which the cost value exceeds a costthreshold; determining (432) a set of remaining clusters among theclusters after removing the selected set of destination points from theclusters (C1-C4), a respective remaining cluster comprising at least onedestination point; and determining (433) the set of stopping positionsas a function of the set of remaining clusters.

Clause 7. The method of clause 6, wherein said determining (433) the setof stopping positions as a function of the set of remaining clusterscomprises: setting, for the respective remaining cluster, a stoppingposition (402′) in relation to the reference position of the respectiveremaining cluster.

Clause 8. The method of clause 6 or 7, wherein the evaluating (423)further comprises: associating (434) the selected set of destinationpoints with a corresponding set of closest predefined positions amongthe predefined positions; identifying (435), based on a cost criterion,a set of candidate storage positions among the set of closest predefinedpositions; operating (436) a further clustering algorithm on the set ofcandidate storage positions to generate one or more storage clusters(N1, N2), and determining (437) a selected storage position (401′) for arespective storage cluster among the one or more storage clusters (N1,N2).

Clause 9. The method of clause 8, wherein the evaluating (423) furthercomprises: assigning (438) the selected storage position (401′) to alldestination points associated with the respective storage cluster (N1,N2).

Clause 10. The method of clause 8 or 9, wherein the selected storageposition (401′) is determined, for the respective storage cluster (N1,N2), as a function of at least one of: a distance from a respectivecandidate storage position in the respective storage cluster (N1, N2) toa reference point (N1′, N2′) of the respective storage cluster (N1, N2),or a number of destination points associated with a respective candidatestorage position in the respective storage cluster (N1, N2).

Clause 11. The method of any one of clauses 6-10, further comprising:determining the cost threshold for the respective destination pointamong the destination points, wherein said determining the costthreshold comprises: determining candidate cost values fortransportation between the respective destination point and thepredefined positions of the first storages (400, 401), and setting thecost threshold as a function of the candidate cost values.

Clause 12. The method of any one of clauses 5-11, wherein the cost valuecorresponds to an estimated energy consumption.

Clause 13. The method of any one of clauses 5-12, further comprising:determining a center point of the respective cluster (C1-C4), andsetting the reference position (C1′-C4′) in relation to the centerpoint.

Clause 14. The method of any preceding clause, wherein the clusteringalgorithm is configured to generate a predefined number of clusters.

Clause 15. The method of any preceding clause, further comprising:providing (411) instructions to arrange the at least one second storagein the set of stopping positions in a first time interval, and providing(412) instructions to transport a subset of the goods to the at leastone second storage in the set of stopping positions in a second timeinterval subsequent to the first time interval.

Clause 16. A computer-readable medium comprising computer instructions(1102A) which, when executed by a processing system (1101), cause theprocessing system (1101) to perform the method of any one of clauses1-15.

Clause 17. A control system configured to perform the method of any oneof clauses 1-15 and comprising a communication device (1103) forcommunicating with the second storages (402).

The structures and methods disclosed herein may be implemented byhardware or a combination of software and hardware. In some embodiments,such hardware comprises one or more software-controlled computersystems. FIG. 37 schematically depicts such a computer system 1100,which comprises a processing system 1101, computer memory 1102, and acommunication interface or device 1103 for input and/or output of data.Depending on implementation, the computer system 1100 may be included inan UAV, in any external computing resource in communication with an UAV,or any other computing resource. The communication interface 1103 may beconfigured for wired and/or wireless communication. The processingsystem 1101 may e.g. include one or more of a CPU (“Central ProcessingUnit”), a DSP (“Digital Signal Processor”), a microprocessor, amicrocontroller, an ASIC (“Application-Specific Integrated Circuit”), acombination of discrete analog and/or digital components, or some otherprogrammable logical device, such as an FPGA (“Field Programmable GateArray”). A control program 1102A comprising computer instructions isstored in the memory 1102 and executed by the processing system 1101 toperform any of the methods, operations, functions or steps exemplifiedin the foregoing. As indicated in FIG. 37, the memory 1102 may alsostore control data 102B for use by the processing system 1102. Thecontrol program 1102A may be supplied to the computer system 1100 on acomputer-readable medium 1110, which may be a tangible (non-transitory)product (e.g. magnetic medium, optical disk, read-only memory, flashmemory, etc.) or a propagating signal.

While the subject of the present disclosure has been described inconnection with what is presently considered to be the most practicalembodiments, it is to be understood that the subject of the presentdisclosure is not to be limited to the disclosed embodiments, but on thecontrary, is intended to cover various modifications and equivalentarrangements included within the spirit and the scope of the appendedclaims.

Further, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. In certain circumstances, parallel processing may beadvantageous.

As noted, any and all combinations of the above-described concepts andembodiments are possible and may provide synergies. A few non-limitingexamples are presented below. The embodiments presented in Chapter 1 maybe combined with any of the embodiments presented in Chapters 2-5 toensure safeguarded delivery of goods. The embodiments for improvingutilization presented in Chapter 2 may be combined with the embodimentsfor safeguarded delivery presented in Chapter 1 to minimize the amountof lost/damaged goods, for example by including in the utilization costthe predicted risk of the goods being lost/damaged at a certaingeographical position or sub-region. The embodiments presented inChapter 2 may also be combined with the embodiments for controlling agroup of UAVs presented in Chapter 4, for example by using the swarmposition/direction as input to the computation of the aggregated costdata. The embodiments presented in Chapter 2 may also be combined withthe embodiments for improved launching of UAVs presented in Chapter 3,for example by including the launch position and the altitude of therespective UAV being launched in the computation of the aggregated costdata. The embodiments for controlling a group of UAVs presented inChapter 4 may be combined with the embodiments for improved launching ofUAVs presented in Chapter 3 and/or the embodiments for configuring adelivery system presented in Chapter 5, for example to launch a swarm ofUAVs from a launch station and/or a nest for further increased flight.The embodiments for configuring a delivery system presented in Chapter 5may be combined with the embodiments for improved launching of UAVspresented in Chapter 3, for example by including the respective launchposition as a position of a second storage (mobile nest). Theembodiments presented in Chapter 5 may also be combined with theembodiments for safeguarded delivery presented in Chapter 1, for exampleto select a specific location for the second storage at the stoppingposition, for example by treating the second storage as a payload forsafeguarded delivery.

1. A method of delivering a payload by an unmanned aerial vehicle (UAV) said method comprising: obtaining a designated location for delivery of the payload; obtaining at least one payload vulnerability index for the payload; obtaining a pick-up time indicative of a time point when the payload is expected to be retrieved by a recipient; selecting a final delivery area at or near the designated location as a function of the at least one payload vulnerability index and the pick-up time; and operating the UAV to deliver the payload to the final delivery area.
 2. The method of claim 1, wherein the at least one payload vulnerability index represents one or more of a monetary value, a temperature sensitivity, an acceptable range of storage temperatures, a moisture sensitivity, or a wind sensitivity.
 3. The method of claim 1, wherein said selecting comprises: predicting an environmental condition in a set of candidate delivery areas, which are located within proximity of the designated location, the environmental condition being predicted for a residence time period that extends from an estimated delivery time to the pick-up time, and selecting the final delivery area among the set of candidate delivery areas as a function of the predicted environmental condition and the at least one payload vulnerability index.
 4. The method of claim 3, wherein the environmental condition comprises at least one of an exposure to sunlight, an exposure to moisture, and an exposure to wind.
 5. The method of claim 3, wherein the environmental condition is predicted based on a three-dimensional model of a region surrounding the designated location and weather data for the region in the residence time period.
 6. The method of claim 3, wherein the environmental condition is predicted based on sensor data from a sensor device on the UAV, or on another UAV.
 7. The method of claim 6, wherein the sensor data comprises at least one two-dimensional representation taken in proximity of the designated location.
 8. The method of claim 3, wherein the final delivery area is further selected based on input data which is supplied by the recipient and indicative of at least one candidate area in the set of candidate delivery areas.
 9. The method of claim 8, wherein the input data comprises one or more of a photographic reproduction and a textual description.
 10. The method of claim 1, further comprising: operating an imaging device on the UAV to capture at least one image of the final delivery area in accordance with at least one image criterion.
 11. The method of claim 10, wherein the at least one image criterion is indicative of one or more objectively identifiable characteristics to be included in the at least one image.
 12. The method of claim 10, further comprising: providing the at least one image for display to the recipient in real time or substantially in real time.
 13. The method of claim 10, further comprising: enabling external control, for the recipient, of at least one of the imaging device or a flight controller of the UAV while providing the at least one image for display in real time.
 14. The method of claim 10, further comprising: operating the UAV to capture images of the final delivery area, while moving at least one of the UAV and the imaging device, until the at least one image is deemed to match a predefined image.
 15. The method of claim 10, wherein the at least one image is captured after delivery of the payload to the final delivery area to include the payload.
 16. A control system comprising logic configured to perform the method of claim
 1. 17. An unmanned aerial vehicle, configured to perform operations comprising: obtain a designated location for delivery of a payload; obtain at least one payload vulnerability index for the payload; obtain a pick-up time indicative of a time point when the payload is expected to be retrieved by a recipient; select a final delivery area at or near the designated location as a function of the at least one payload vulnerability index and the pick-up time; and deliver the payload to the final delivery area.
 18. The unmanned aerial vehicle of claim 17, which is further configured to perform operations comprising: predict an environmental condition in a set of candidate delivery areas, which are located within proximity of the designated location, the environmental condition being predicted for a residence time period that extends from an estimated delivery time to the pick-up time; and select the final delivery area among the set of candidate delivery areas as a function of the predicted environmental condition and the at least one payload vulnerability index.
 19. The unmanned aerial vehicle of claim 18, which is further configured to predict the environmental condition based on sensor data from a sensor device on the unmanned aerial vehicle, or on another unmanned aerial vehicle.
 20. The unmanned aerial vehicle of claim 17, which is further configured to operate an imaging device on the unmanned aerial vehicle to capture at least one image of the final delivery area in accordance with at least one image criterion. 